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ckpts/universal/global_step80/zero/10.mlp.dense_h_to_4h.weight/exp_avg.pt

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ckpts/universal/global_step80/zero/16.attention.dense.weight/exp_avg.pt

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ckpts/universal/global_step80/zero/26.attention.query_key_value.weight/exp_avg_sq.pt

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+size 50332843

venv/lib/python3.10/site-packages/networkx/classes/coreviews.py

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+"""Views of core data structures such as nested Mappings (e.g. dict-of-dicts).
+These ``Views`` often restrict element access, with either the entire view or
+layers of nested mappings being read-only.
+"""
+from collections.abc import Mapping
+
+__all__ = [
+    "AtlasView",
+    "AdjacencyView",
+    "MultiAdjacencyView",
+    "UnionAtlas",
+    "UnionAdjacency",
+    "UnionMultiInner",
+    "UnionMultiAdjacency",
+    "FilterAtlas",
+    "FilterAdjacency",
+    "FilterMultiInner",
+    "FilterMultiAdjacency",
+]
+
+
+class AtlasView(Mapping):
+    """An AtlasView is a Read-only Mapping of Mappings.
+
+    It is a View into a dict-of-dict data structure.
+    The inner level of dict is read-write. But the
+    outer level is read-only.
+
+    See Also
+    ========
+    AdjacencyView: View into dict-of-dict-of-dict
+    MultiAdjacencyView: View into dict-of-dict-of-dict-of-dict
+    """
+
+    __slots__ = ("_atlas",)
+
+    def __getstate__(self):
+        return {"_atlas": self._atlas}
+
+    def __setstate__(self, state):
+        self._atlas = state["_atlas"]
+
+    def __init__(self, d):
+        self._atlas = d
+
+    def __len__(self):
+        return len(self._atlas)
+
+    def __iter__(self):
+        return iter(self._atlas)
+
+    def __getitem__(self, key):
+        return self._atlas[key]
+
+    def copy(self):
+        return {n: self[n].copy() for n in self._atlas}
+
+    def __str__(self):
+        return str(self._atlas)  # {nbr: self[nbr] for nbr in self})
+
+    def __repr__(self):
+        return f"{self.__class__.__name__}({self._atlas!r})"
+
+
+class AdjacencyView(AtlasView):
+    """An AdjacencyView is a Read-only Map of Maps of Maps.
+
+    It is a View into a dict-of-dict-of-dict data structure.
+    The inner level of dict is read-write. But the
+    outer levels are read-only.
+
+    See Also
+    ========
+    AtlasView: View into dict-of-dict
+    MultiAdjacencyView: View into dict-of-dict-of-dict-of-dict
+    """
+
+    __slots__ = ()  # Still uses AtlasView slots names _atlas
+
+    def __getitem__(self, name):
+        return AtlasView(self._atlas[name])
+
+    def copy(self):
+        return {n: self[n].copy() for n in self._atlas}
+
+
+class MultiAdjacencyView(AdjacencyView):
+    """An MultiAdjacencyView is a Read-only Map of Maps of Maps of Maps.
+
+    It is a View into a dict-of-dict-of-dict-of-dict data structure.
+    The inner level of dict is read-write. But the
+    outer levels are read-only.
+
+    See Also
+    ========
+    AtlasView: View into dict-of-dict
+    AdjacencyView: View into dict-of-dict-of-dict
+    """
+
+    __slots__ = ()  # Still uses AtlasView slots names _atlas
+
+    def __getitem__(self, name):
+        return AdjacencyView(self._atlas[name])
+
+    def copy(self):
+        return {n: self[n].copy() for n in self._atlas}
+
+
+class UnionAtlas(Mapping):
+    """A read-only union of two atlases (dict-of-dict).
+
+    The two dict-of-dicts represent the inner dict of
+    an Adjacency:  `G.succ[node]` and `G.pred[node]`.
+    The inner level of dict of both hold attribute key:value
+    pairs and is read-write. But the outer level is read-only.
+
+    See Also
+    ========
+    UnionAdjacency: View into dict-of-dict-of-dict
+    UnionMultiAdjacency: View into dict-of-dict-of-dict-of-dict
+    """
+
+    __slots__ = ("_succ", "_pred")
+
+    def __getstate__(self):
+        return {"_succ": self._succ, "_pred": self._pred}
+
+    def __setstate__(self, state):
+        self._succ = state["_succ"]
+        self._pred = state["_pred"]
+
+    def __init__(self, succ, pred):
+        self._succ = succ
+        self._pred = pred
+
+    def __len__(self):
+        return len(self._succ.keys() | self._pred.keys())
+
+    def __iter__(self):
+        return iter(set(self._succ.keys()) | set(self._pred.keys()))
+
+    def __getitem__(self, key):
+        try:
+            return self._succ[key]
+        except KeyError:
+            return self._pred[key]
+
+    def copy(self):
+        result = {nbr: dd.copy() for nbr, dd in self._succ.items()}
+        for nbr, dd in self._pred.items():
+            if nbr in result:
+                result[nbr].update(dd)
+            else:
+                result[nbr] = dd.copy()
+        return result
+
+    def __str__(self):
+        return str({nbr: self[nbr] for nbr in self})
+
+    def __repr__(self):
+        return f"{self.__class__.__name__}({self._succ!r}, {self._pred!r})"
+
+
+class UnionAdjacency(Mapping):
+    """A read-only union of dict Adjacencies as a Map of Maps of Maps.
+
+    The two input dict-of-dict-of-dicts represent the union of
+    `G.succ` and `G.pred`. Return values are UnionAtlas
+    The inner level of dict is read-write. But the
+    middle and outer levels are read-only.
+
+    succ : a dict-of-dict-of-dict {node: nbrdict}
+    pred : a dict-of-dict-of-dict {node: nbrdict}
+    The keys for the two dicts should be the same
+
+    See Also
+    ========
+    UnionAtlas: View into dict-of-dict
+    UnionMultiAdjacency: View into dict-of-dict-of-dict-of-dict
+    """
+
+    __slots__ = ("_succ", "_pred")
+
+    def __getstate__(self):
+        return {"_succ": self._succ, "_pred": self._pred}
+
+    def __setstate__(self, state):
+        self._succ = state["_succ"]
+        self._pred = state["_pred"]
+
+    def __init__(self, succ, pred):
+        # keys must be the same for two input dicts
+        assert len(set(succ.keys()) ^ set(pred.keys())) == 0
+        self._succ = succ
+        self._pred = pred
+
+    def __len__(self):
+        return len(self._succ)  # length of each dict should be the same
+
+    def __iter__(self):
+        return iter(self._succ)
+
+    def __getitem__(self, nbr):
+        return UnionAtlas(self._succ[nbr], self._pred[nbr])
+
+    def copy(self):
+        return {n: self[n].copy() for n in self._succ}
+
+    def __str__(self):
+        return str({nbr: self[nbr] for nbr in self})
+
+    def __repr__(self):
+        return f"{self.__class__.__name__}({self._succ!r}, {self._pred!r})"
+
+
+class UnionMultiInner(UnionAtlas):
+    """A read-only union of two inner dicts of MultiAdjacencies.
+
+    The two input dict-of-dict-of-dicts represent the union of
+    `G.succ[node]` and `G.pred[node]` for MultiDiGraphs.
+    Return values are UnionAtlas.
+    The inner level of dict is read-write. But the outer levels are read-only.
+
+    See Also
+    ========
+    UnionAtlas: View into dict-of-dict
+    UnionAdjacency:  View into dict-of-dict-of-dict
+    UnionMultiAdjacency:  View into dict-of-dict-of-dict-of-dict
+    """
+
+    __slots__ = ()  # Still uses UnionAtlas slots names _succ, _pred
+
+    def __getitem__(self, node):
+        in_succ = node in self._succ
+        in_pred = node in self._pred
+        if in_succ:
+            if in_pred:
+                return UnionAtlas(self._succ[node], self._pred[node])
+            return UnionAtlas(self._succ[node], {})
+        return UnionAtlas({}, self._pred[node])
+
+    def copy(self):
+        nodes = set(self._succ.keys()) | set(self._pred.keys())
+        return {n: self[n].copy() for n in nodes}
+
+
+class UnionMultiAdjacency(UnionAdjacency):
+    """A read-only union of two dict MultiAdjacencies.
+
+    The two input dict-of-dict-of-dict-of-dicts represent the union of
+    `G.succ` and `G.pred` for MultiDiGraphs. Return values are UnionAdjacency.
+    The inner level of dict is read-write. But the outer levels are read-only.
+
+    See Also
+    ========
+    UnionAtlas:  View into dict-of-dict
+    UnionMultiInner:  View into dict-of-dict-of-dict
+    """
+
+    __slots__ = ()  # Still uses UnionAdjacency slots names _succ, _pred
+
+    def __getitem__(self, node):
+        return UnionMultiInner(self._succ[node], self._pred[node])
+
+
+class FilterAtlas(Mapping):  # nodedict, nbrdict, keydict
+    """A read-only Mapping of Mappings with filtering criteria for nodes.
+
+    It is a view into a dict-of-dict data structure, and it selects only
+    nodes that meet the criteria defined by ``NODE_OK``.
+
+    See Also
+    ========
+    FilterAdjacency
+    FilterMultiInner
+    FilterMultiAdjacency
+    """
+
+    def __init__(self, d, NODE_OK):
+        self._atlas = d
+        self.NODE_OK = NODE_OK
+
+    def __len__(self):
+        return sum(1 for n in self)
+
+    def __iter__(self):
+        try:  # check that NODE_OK has attr 'nodes'
+            node_ok_shorter = 2 * len(self.NODE_OK.nodes) < len(self._atlas)
+        except AttributeError:
+            node_ok_shorter = False
+        if node_ok_shorter:
+            return (n for n in self.NODE_OK.nodes if n in self._atlas)
+        return (n for n in self._atlas if self.NODE_OK(n))
+
+    def __getitem__(self, key):
+        if key in self._atlas and self.NODE_OK(key):
+            return self._atlas[key]
+        raise KeyError(f"Key {key} not found")
+
+    def __str__(self):
+        return str({nbr: self[nbr] for nbr in self})
+
+    def __repr__(self):
+        return f"{self.__class__.__name__}({self._atlas!r}, {self.NODE_OK!r})"
+
+
+class FilterAdjacency(Mapping):  # edgedict
+    """A read-only Mapping of Mappings with filtering criteria for nodes and edges.
+
+    It is a view into a dict-of-dict-of-dict data structure, and it selects nodes
+    and edges that satisfy specific criteria defined by ``NODE_OK`` and ``EDGE_OK``,
+    respectively.
+
+    See Also
+    ========
+    FilterAtlas
+    FilterMultiInner
+    FilterMultiAdjacency
+    """
+
+    def __init__(self, d, NODE_OK, EDGE_OK):
+        self._atlas = d
+        self.NODE_OK = NODE_OK
+        self.EDGE_OK = EDGE_OK
+
+    def __len__(self):
+        return sum(1 for n in self)
+
+    def __iter__(self):
+        try:  # check that NODE_OK has attr 'nodes'
+            node_ok_shorter = 2 * len(self.NODE_OK.nodes) < len(self._atlas)
+        except AttributeError:
+            node_ok_shorter = False
+        if node_ok_shorter:
+            return (n for n in self.NODE_OK.nodes if n in self._atlas)
+        return (n for n in self._atlas if self.NODE_OK(n))
+
+    def __getitem__(self, node):
+        if node in self._atlas and self.NODE_OK(node):
+
+            def new_node_ok(nbr):
+                return self.NODE_OK(nbr) and self.EDGE_OK(node, nbr)
+
+            return FilterAtlas(self._atlas[node], new_node_ok)
+        raise KeyError(f"Key {node} not found")
+
+    def __str__(self):
+        return str({nbr: self[nbr] for nbr in self})
+
+    def __repr__(self):
+        name = self.__class__.__name__
+        return f"{name}({self._atlas!r}, {self.NODE_OK!r}, {self.EDGE_OK!r})"
+
+
+class FilterMultiInner(FilterAdjacency):  # muliedge_seconddict
+    """A read-only Mapping of Mappings with filtering criteria for nodes and edges.
+
+    It is a view into a dict-of-dict-of-dict-of-dict data structure, and it selects nodes
+    and edges that meet specific criteria defined by ``NODE_OK`` and ``EDGE_OK``.
+
+    See Also
+    ========
+    FilterAtlas
+    FilterAdjacency
+    FilterMultiAdjacency
+    """
+
+    def __iter__(self):
+        try:  # check that NODE_OK has attr 'nodes'
+            node_ok_shorter = 2 * len(self.NODE_OK.nodes) < len(self._atlas)
+        except AttributeError:
+            node_ok_shorter = False
+        if node_ok_shorter:
+            my_nodes = (n for n in self.NODE_OK.nodes if n in self._atlas)
+        else:
+            my_nodes = (n for n in self._atlas if self.NODE_OK(n))
+        for n in my_nodes:
+            some_keys_ok = False
+            for key in self._atlas[n]:
+                if self.EDGE_OK(n, key):
+                    some_keys_ok = True
+                    break
+            if some_keys_ok is True:
+                yield n
+
+    def __getitem__(self, nbr):
+        if nbr in self._atlas and self.NODE_OK(nbr):
+
+            def new_node_ok(key):
+                return self.EDGE_OK(nbr, key)
+
+            return FilterAtlas(self._atlas[nbr], new_node_ok)
+        raise KeyError(f"Key {nbr} not found")
+
+
+class FilterMultiAdjacency(FilterAdjacency):  # multiedgedict
+    """A read-only Mapping of Mappings with filtering criteria
+    for nodes and edges.
+
+    It is a view into a dict-of-dict-of-dict-of-dict data structure,
+    and it selects nodes and edges that satisfy specific criteria
+    defined by ``NODE_OK`` and ``EDGE_OK``, respectively.
+
+    See Also
+    ========
+    FilterAtlas
+    FilterAdjacency
+    FilterMultiInner
+    """
+
+    def __getitem__(self, node):
+        if node in self._atlas and self.NODE_OK(node):
+
+            def edge_ok(nbr, key):
+                return self.NODE_OK(nbr) and self.EDGE_OK(node, nbr, key)
+
+            return FilterMultiInner(self._atlas[node], self.NODE_OK, edge_ok)
+        raise KeyError(f"Key {node} not found")

venv/lib/python3.10/site-packages/networkx/classes/reportviews.py

@@ -0,0 +1,1438 @@
+"""
+View Classes provide node, edge and degree "views" of a graph.
+
+Views for nodes, edges and degree are provided for all base graph classes.
+A view means a read-only object that is quick to create, automatically
+updated when the graph changes, and provides basic access like `n in V`,
+`for n in V`, `V[n]` and sometimes set operations.
+
+The views are read-only iterable containers that are updated as the
+graph is updated. As with dicts, the graph should not be updated
+while iterating through the view. Views can be iterated multiple times.
+
+Edge and Node views also allow data attribute lookup.
+The resulting attribute dict is writable as `G.edges[3, 4]['color']='red'`
+Degree views allow lookup of degree values for single nodes.
+Weighted degree is supported with the `weight` argument.
+
+NodeView
+========
+
+    `V = G.nodes` (or `V = G.nodes()`) allows `len(V)`, `n in V`, set
+    operations e.g. "G.nodes & H.nodes", and `dd = G.nodes[n]`, where
+    `dd` is the node data dict. Iteration is over the nodes by default.
+
+NodeDataView
+============
+
+    To iterate over (node, data) pairs, use arguments to `G.nodes()`
+    to create a DataView e.g. `DV = G.nodes(data='color', default='red')`.
+    The DataView iterates as `for n, color in DV` and allows
+    `(n, 'red') in DV`. Using `DV = G.nodes(data=True)`, the DataViews
+    use the full datadict in writeable form also allowing contain testing as
+    `(n, {'color': 'red'}) in VD`. DataViews allow set operations when
+    data attributes are hashable.
+
+DegreeView
+==========
+
+    `V = G.degree` allows iteration over (node, degree) pairs as well
+    as lookup: `deg=V[n]`. There are many flavors of DegreeView
+    for In/Out/Directed/Multi. For Directed Graphs, `G.degree`
+    counts both in and out going edges. `G.out_degree` and
+    `G.in_degree` count only specific directions.
+    Weighted degree using edge data attributes is provide via
+    `V = G.degree(weight='attr_name')` where any string with the
+    attribute name can be used. `weight=None` is the default.
+    No set operations are implemented for degrees, use NodeView.
+
+    The argument `nbunch` restricts iteration to nodes in nbunch.
+    The DegreeView can still lookup any node even if nbunch is specified.
+
+EdgeView
+========
+
+    `V = G.edges` or `V = G.edges()` allows iteration over edges as well as
+    `e in V`, set operations and edge data lookup `dd = G.edges[2, 3]`.
+    Iteration is over 2-tuples `(u, v)` for Graph/DiGraph. For multigraphs
+    edges 3-tuples `(u, v, key)` are the default but 2-tuples can be obtained
+    via `V = G.edges(keys=False)`.
+
+    Set operations for directed graphs treat the edges as a set of 2-tuples.
+    For undirected graphs, 2-tuples are not a unique representation of edges.
+    So long as the set being compared to contains unique representations
+    of its edges, the set operations will act as expected. If the other
+    set contains both `(0, 1)` and `(1, 0)` however, the result of set
+    operations may contain both representations of the same edge.
+
+EdgeDataView
+============
+
+    Edge data can be reported using an EdgeDataView typically created
+    by calling an EdgeView: `DV = G.edges(data='weight', default=1)`.
+    The EdgeDataView allows iteration over edge tuples, membership checking
+    but no set operations.
+
+    Iteration depends on `data` and `default` and for multigraph `keys`
+    If `data is False` (the default) then iterate over 2-tuples `(u, v)`.
+    If `data is True` iterate over 3-tuples `(u, v, datadict)`.
+    Otherwise iterate over `(u, v, datadict.get(data, default))`.
+    For Multigraphs, if `keys is True`, replace `u, v` with `u, v, key`
+    to create 3-tuples and 4-tuples.
+
+    The argument `nbunch` restricts edges to those incident to nodes in nbunch.
+"""
+from collections.abc import Mapping, Set
+
+import networkx as nx
+
+__all__ = [
+    "NodeView",
+    "NodeDataView",
+    "EdgeView",
+    "OutEdgeView",
+    "InEdgeView",
+    "EdgeDataView",
+    "OutEdgeDataView",
+    "InEdgeDataView",
+    "MultiEdgeView",
+    "OutMultiEdgeView",
+    "InMultiEdgeView",
+    "MultiEdgeDataView",
+    "OutMultiEdgeDataView",
+    "InMultiEdgeDataView",
+    "DegreeView",
+    "DiDegreeView",
+    "InDegreeView",
+    "OutDegreeView",
+    "MultiDegreeView",
+    "DiMultiDegreeView",
+    "InMultiDegreeView",
+    "OutMultiDegreeView",
+]
+
+
+# NodeViews
+class NodeView(Mapping, Set):
+    """A NodeView class to act as G.nodes for a NetworkX Graph
+
+    Set operations act on the nodes without considering data.
+    Iteration is over nodes. Node data can be looked up like a dict.
+    Use NodeDataView to iterate over node data or to specify a data
+    attribute for lookup. NodeDataView is created by calling the NodeView.
+
+    Parameters
+    ----------
+    graph : NetworkX graph-like class
+
+    Examples
+    --------
+    >>> G = nx.path_graph(3)
+    >>> NV = G.nodes()
+    >>> 2 in NV
+    True
+    >>> for n in NV:
+    ...     print(n)
+    0
+    1
+    2
+    >>> assert NV & {1, 2, 3} == {1, 2}
+
+    >>> G.add_node(2, color="blue")
+    >>> NV[2]
+    {'color': 'blue'}
+    >>> G.add_node(8, color="red")
+    >>> NDV = G.nodes(data=True)
+    >>> (2, NV[2]) in NDV
+    True
+    >>> for n, dd in NDV:
+    ...     print((n, dd.get("color", "aqua")))
+    (0, 'aqua')
+    (1, 'aqua')
+    (2, 'blue')
+    (8, 'red')
+    >>> NDV[2] == NV[2]
+    True
+
+    >>> NVdata = G.nodes(data="color", default="aqua")
+    >>> (2, NVdata[2]) in NVdata
+    True
+    >>> for n, dd in NVdata:
+    ...     print((n, dd))
+    (0, 'aqua')
+    (1, 'aqua')
+    (2, 'blue')
+    (8, 'red')
+    >>> NVdata[2] == NV[2]  # NVdata gets 'color', NV gets datadict
+    False
+    """
+
+    __slots__ = ("_nodes",)
+
+    def __getstate__(self):
+        return {"_nodes": self._nodes}
+
+    def __setstate__(self, state):
+        self._nodes = state["_nodes"]
+
+    def __init__(self, graph):
+        self._nodes = graph._node
+
+    # Mapping methods
+    def __len__(self):
+        return len(self._nodes)
+
+    def __iter__(self):
+        return iter(self._nodes)
+
+    def __getitem__(self, n):
+        if isinstance(n, slice):
+            raise nx.NetworkXError(
+                f"{type(self).__name__} does not support slicing, "
+                f"try list(G.nodes)[{n.start}:{n.stop}:{n.step}]"
+            )
+        return self._nodes[n]
+
+    # Set methods
+    def __contains__(self, n):
+        return n in self._nodes
+
+    @classmethod
+    def _from_iterable(cls, it):
+        return set(it)
+
+    # DataView method
+    def __call__(self, data=False, default=None):
+        if data is False:
+            return self
+        return NodeDataView(self._nodes, data, default)
+
+    def data(self, data=True, default=None):
+        """
+        Return a read-only view of node data.
+
+        Parameters
+        ----------
+        data : bool or node data key, default=True
+            If ``data=True`` (the default), return a `NodeDataView` object that
+            maps each node to *all* of its attributes. `data` may also be an
+            arbitrary key, in which case the `NodeDataView` maps each node to
+            the value for the keyed attribute. In this case, if a node does
+            not have the `data` attribute, the `default` value is used.
+        default : object, default=None
+            The value used when a node does not have a specific attribute.
+
+        Returns
+        -------
+        NodeDataView
+            The layout of the returned NodeDataView depends on the value of the
+            `data` parameter.
+
+        Notes
+        -----
+        If ``data=False``, returns a `NodeView` object without data.
+
+        See Also
+        --------
+        NodeDataView
+
+        Examples
+        --------
+        >>> G = nx.Graph()
+        >>> G.add_nodes_from(
+        ...     [
+        ...         (0, {"color": "red", "weight": 10}),
+        ...         (1, {"color": "blue"}),
+        ...         (2, {"color": "yellow", "weight": 2}),
+        ...     ]
+        ... )
+
+        Accessing node data with ``data=True`` (the default) returns a
+        NodeDataView mapping each node to all of its attributes:
+
+        >>> G.nodes.data()
+        NodeDataView({0: {'color': 'red', 'weight': 10}, 1: {'color': 'blue'}, 2: {'color': 'yellow', 'weight': 2}})
+
+        If `data` represents  a key in the node attribute dict, a NodeDataView mapping
+        the nodes to the value for that specific key is returned:
+
+        >>> G.nodes.data("color")
+        NodeDataView({0: 'red', 1: 'blue', 2: 'yellow'}, data='color')
+
+        If a specific key is not found in an attribute dict, the value specified
+        by `default` is returned:
+
+        >>> G.nodes.data("weight", default=-999)
+        NodeDataView({0: 10, 1: -999, 2: 2}, data='weight')
+
+        Note that there is no check that the `data` key is in any of the
+        node attribute dictionaries:
+
+        >>> G.nodes.data("height")
+        NodeDataView({0: None, 1: None, 2: None}, data='height')
+        """
+        if data is False:
+            return self
+        return NodeDataView(self._nodes, data, default)
+
+    def __str__(self):
+        return str(list(self))
+
+    def __repr__(self):
+        return f"{self.__class__.__name__}({tuple(self)})"
+
+
+class NodeDataView(Set):
+    """A DataView class for nodes of a NetworkX Graph
+
+    The main use for this class is to iterate through node-data pairs.
+    The data can be the entire data-dictionary for each node, or it
+    can be a specific attribute (with default) for each node.
+    Set operations are enabled with NodeDataView, but don't work in
+    cases where the data is not hashable. Use with caution.
+    Typically, set operations on nodes use NodeView, not NodeDataView.
+    That is, they use `G.nodes` instead of `G.nodes(data='foo')`.
+
+    Parameters
+    ==========
+    graph : NetworkX graph-like class
+    data : bool or string (default=False)
+    default : object (default=None)
+    """
+
+    __slots__ = ("_nodes", "_data", "_default")
+
+    def __getstate__(self):
+        return {"_nodes": self._nodes, "_data": self._data, "_default": self._default}
+
+    def __setstate__(self, state):
+        self._nodes = state["_nodes"]
+        self._data = state["_data"]
+        self._default = state["_default"]
+
+    def __init__(self, nodedict, data=False, default=None):
+        self._nodes = nodedict
+        self._data = data
+        self._default = default
+
+    @classmethod
+    def _from_iterable(cls, it):
+        try:
+            return set(it)
+        except TypeError as err:
+            if "unhashable" in str(err):
+                msg = " : Could be b/c data=True or your values are unhashable"
+                raise TypeError(str(err) + msg) from err
+            raise
+
+    def __len__(self):
+        return len(self._nodes)
+
+    def __iter__(self):
+        data = self._data
+        if data is False:
+            return iter(self._nodes)
+        if data is True:
+            return iter(self._nodes.items())
+        return (
+            (n, dd[data] if data in dd else self._default)
+            for n, dd in self._nodes.items()
+        )
+
+    def __contains__(self, n):
+        try:
+            node_in = n in self._nodes
+        except TypeError:
+            n, d = n
+            return n in self._nodes and self[n] == d
+        if node_in is True:
+            return node_in
+        try:
+            n, d = n
+        except (TypeError, ValueError):
+            return False
+        return n in self._nodes and self[n] == d
+
+    def __getitem__(self, n):
+        if isinstance(n, slice):
+            raise nx.NetworkXError(
+                f"{type(self).__name__} does not support slicing, "
+                f"try list(G.nodes.data())[{n.start}:{n.stop}:{n.step}]"
+            )
+        ddict = self._nodes[n]
+        data = self._data
+        if data is False or data is True:
+            return ddict
+        return ddict[data] if data in ddict else self._default
+
+    def __str__(self):
+        return str(list(self))
+
+    def __repr__(self):
+        name = self.__class__.__name__
+        if self._data is False:
+            return f"{name}({tuple(self)})"
+        if self._data is True:
+            return f"{name}({dict(self)})"
+        return f"{name}({dict(self)}, data={self._data!r})"
+
+
+# DegreeViews
+class DiDegreeView:
+    """A View class for degree of nodes in a NetworkX Graph
+
+    The functionality is like dict.items() with (node, degree) pairs.
+    Additional functionality includes read-only lookup of node degree,
+    and calling with optional features nbunch (for only a subset of nodes)
+    and weight (use edge weights to compute degree).
+
+    Parameters
+    ==========
+    graph : NetworkX graph-like class
+    nbunch : node, container of nodes, or None meaning all nodes (default=None)
+    weight : bool or string (default=None)
+
+    Notes
+    -----
+    DegreeView can still lookup any node even if nbunch is specified.
+
+    Examples
+    --------
+    >>> G = nx.path_graph(3)
+    >>> DV = G.degree()
+    >>> assert DV[2] == 1
+    >>> assert sum(deg for n, deg in DV) == 4
+
+    >>> DVweight = G.degree(weight="span")
+    >>> G.add_edge(1, 2, span=34)
+    >>> DVweight[2]
+    34
+    >>> DVweight[0]  #  default edge weight is 1
+    1
+    >>> sum(span for n, span in DVweight)  # sum weighted degrees
+    70
+
+    >>> DVnbunch = G.degree(nbunch=(1, 2))
+    >>> assert len(list(DVnbunch)) == 2  # iteration over nbunch only
+    """
+
+    def __init__(self, G, nbunch=None, weight=None):
+        self._graph = G
+        self._succ = G._succ if hasattr(G, "_succ") else G._adj
+        self._pred = G._pred if hasattr(G, "_pred") else G._adj
+        self._nodes = self._succ if nbunch is None else list(G.nbunch_iter(nbunch))
+        self._weight = weight
+
+    def __call__(self, nbunch=None, weight=None):
+        if nbunch is None:
+            if weight == self._weight:
+                return self
+            return self.__class__(self._graph, None, weight)
+        try:
+            if nbunch in self._nodes:
+                if weight == self._weight:
+                    return self[nbunch]
+                return self.__class__(self._graph, None, weight)[nbunch]
+        except TypeError:
+            pass
+        return self.__class__(self._graph, nbunch, weight)
+
+    def __getitem__(self, n):
+        weight = self._weight
+        succs = self._succ[n]
+        preds = self._pred[n]
+        if weight is None:
+            return len(succs) + len(preds)
+        return sum(dd.get(weight, 1) for dd in succs.values()) + sum(
+            dd.get(weight, 1) for dd in preds.values()
+        )
+
+    def __iter__(self):
+        weight = self._weight
+        if weight is None:
+            for n in self._nodes:
+                succs = self._succ[n]
+                preds = self._pred[n]
+                yield (n, len(succs) + len(preds))
+        else:
+            for n in self._nodes:
+                succs = self._succ[n]
+                preds = self._pred[n]
+                deg = sum(dd.get(weight, 1) for dd in succs.values()) + sum(
+                    dd.get(weight, 1) for dd in preds.values()
+                )
+                yield (n, deg)
+
+    def __len__(self):
+        return len(self._nodes)
+
+    def __str__(self):
+        return str(list(self))
+
+    def __repr__(self):
+        return f"{self.__class__.__name__}({dict(self)})"
+
+
+class DegreeView(DiDegreeView):
+    """A DegreeView class to act as G.degree for a NetworkX Graph
+
+    Typical usage focuses on iteration over `(node, degree)` pairs.
+    The degree is by default the number of edges incident to the node.
+    Optional argument `weight` enables weighted degree using the edge
+    attribute named in the `weight` argument.  Reporting and iteration
+    can also be restricted to a subset of nodes using `nbunch`.
+
+    Additional functionality include node lookup so that `G.degree[n]`
+    reported the (possibly weighted) degree of node `n`. Calling the
+    view creates a view with different arguments `nbunch` or `weight`.
+
+    Parameters
+    ==========
+    graph : NetworkX graph-like class
+    nbunch : node, container of nodes, or None meaning all nodes (default=None)
+    weight : string or None (default=None)
+
+    Notes
+    -----
+    DegreeView can still lookup any node even if nbunch is specified.
+
+    Examples
+    --------
+    >>> G = nx.path_graph(3)
+    >>> DV = G.degree()
+    >>> assert DV[2] == 1
+    >>> assert G.degree[2] == 1
+    >>> assert sum(deg for n, deg in DV) == 4
+
+    >>> DVweight = G.degree(weight="span")
+    >>> G.add_edge(1, 2, span=34)
+    >>> DVweight[2]
+    34
+    >>> DVweight[0]  #  default edge weight is 1
+    1
+    >>> sum(span for n, span in DVweight)  # sum weighted degrees
+    70
+
+    >>> DVnbunch = G.degree(nbunch=(1, 2))
+    >>> assert len(list(DVnbunch)) == 2  # iteration over nbunch only
+    """
+
+    def __getitem__(self, n):
+        weight = self._weight
+        nbrs = self._succ[n]
+        if weight is None:
+            return len(nbrs) + (n in nbrs)
+        return sum(dd.get(weight, 1) for dd in nbrs.values()) + (
+            n in nbrs and nbrs[n].get(weight, 1)
+        )
+
+    def __iter__(self):
+        weight = self._weight
+        if weight is None:
+            for n in self._nodes:
+                nbrs = self._succ[n]
+                yield (n, len(nbrs) + (n in nbrs))
+        else:
+            for n in self._nodes:
+                nbrs = self._succ[n]
+                deg = sum(dd.get(weight, 1) for dd in nbrs.values()) + (
+                    n in nbrs and nbrs[n].get(weight, 1)
+                )
+                yield (n, deg)
+
+
+class OutDegreeView(DiDegreeView):
+    """A DegreeView class to report out_degree for a DiGraph; See DegreeView"""
+
+    def __getitem__(self, n):
+        weight = self._weight
+        nbrs = self._succ[n]
+        if self._weight is None:
+            return len(nbrs)
+        return sum(dd.get(self._weight, 1) for dd in nbrs.values())
+
+    def __iter__(self):
+        weight = self._weight
+        if weight is None:
+            for n in self._nodes:
+                succs = self._succ[n]
+                yield (n, len(succs))
+        else:
+            for n in self._nodes:
+                succs = self._succ[n]
+                deg = sum(dd.get(weight, 1) for dd in succs.values())
+                yield (n, deg)
+
+
+class InDegreeView(DiDegreeView):
+    """A DegreeView class to report in_degree for a DiGraph; See DegreeView"""
+
+    def __getitem__(self, n):
+        weight = self._weight
+        nbrs = self._pred[n]
+        if weight is None:
+            return len(nbrs)
+        return sum(dd.get(weight, 1) for dd in nbrs.values())
+
+    def __iter__(self):
+        weight = self._weight
+        if weight is None:
+            for n in self._nodes:
+                preds = self._pred[n]
+                yield (n, len(preds))
+        else:
+            for n in self._nodes:
+                preds = self._pred[n]
+                deg = sum(dd.get(weight, 1) for dd in preds.values())
+                yield (n, deg)
+
+
+class MultiDegreeView(DiDegreeView):
+    """A DegreeView class for undirected multigraphs; See DegreeView"""
+
+    def __getitem__(self, n):
+        weight = self._weight
+        nbrs = self._succ[n]
+        if weight is None:
+            return sum(len(keys) for keys in nbrs.values()) + (
+                n in nbrs and len(nbrs[n])
+            )
+        # edge weighted graph - degree is sum of nbr edge weights
+        deg = sum(
+            d.get(weight, 1) for key_dict in nbrs.values() for d in key_dict.values()
+        )
+        if n in nbrs:
+            deg += sum(d.get(weight, 1) for d in nbrs[n].values())
+        return deg
+
+    def __iter__(self):
+        weight = self._weight
+        if weight is None:
+            for n in self._nodes:
+                nbrs = self._succ[n]
+                deg = sum(len(keys) for keys in nbrs.values()) + (
+                    n in nbrs and len(nbrs[n])
+                )
+                yield (n, deg)
+        else:
+            for n in self._nodes:
+                nbrs = self._succ[n]
+                deg = sum(
+                    d.get(weight, 1)
+                    for key_dict in nbrs.values()
+                    for d in key_dict.values()
+                )
+                if n in nbrs:
+                    deg += sum(d.get(weight, 1) for d in nbrs[n].values())
+                yield (n, deg)
+
+
+class DiMultiDegreeView(DiDegreeView):
+    """A DegreeView class for MultiDiGraph; See DegreeView"""
+
+    def __getitem__(self, n):
+        weight = self._weight
+        succs = self._succ[n]
+        preds = self._pred[n]
+        if weight is None:
+            return sum(len(keys) for keys in succs.values()) + sum(
+                len(keys) for keys in preds.values()
+            )
+        # edge weighted graph - degree is sum of nbr edge weights
+        deg = sum(
+            d.get(weight, 1) for key_dict in succs.values() for d in key_dict.values()
+        ) + sum(
+            d.get(weight, 1) for key_dict in preds.values() for d in key_dict.values()
+        )
+        return deg
+
+    def __iter__(self):
+        weight = self._weight
+        if weight is None:
+            for n in self._nodes:
+                succs = self._succ[n]
+                preds = self._pred[n]
+                deg = sum(len(keys) for keys in succs.values()) + sum(
+                    len(keys) for keys in preds.values()
+                )
+                yield (n, deg)
+        else:
+            for n in self._nodes:
+                succs = self._succ[n]
+                preds = self._pred[n]
+                deg = sum(
+                    d.get(weight, 1)
+                    for key_dict in succs.values()
+                    for d in key_dict.values()
+                ) + sum(
+                    d.get(weight, 1)
+                    for key_dict in preds.values()
+                    for d in key_dict.values()
+                )
+                yield (n, deg)
+
+
+class InMultiDegreeView(DiDegreeView):
+    """A DegreeView class for inward degree of MultiDiGraph; See DegreeView"""
+
+    def __getitem__(self, n):
+        weight = self._weight
+        nbrs = self._pred[n]
+        if weight is None:
+            return sum(len(data) for data in nbrs.values())
+        # edge weighted graph - degree is sum of nbr edge weights
+        return sum(
+            d.get(weight, 1) for key_dict in nbrs.values() for d in key_dict.values()
+        )
+
+    def __iter__(self):
+        weight = self._weight
+        if weight is None:
+            for n in self._nodes:
+                nbrs = self._pred[n]
+                deg = sum(len(data) for data in nbrs.values())
+                yield (n, deg)
+        else:
+            for n in self._nodes:
+                nbrs = self._pred[n]
+                deg = sum(
+                    d.get(weight, 1)
+                    for key_dict in nbrs.values()
+                    for d in key_dict.values()
+                )
+                yield (n, deg)
+
+
+class OutMultiDegreeView(DiDegreeView):
+    """A DegreeView class for outward degree of MultiDiGraph; See DegreeView"""
+
+    def __getitem__(self, n):
+        weight = self._weight
+        nbrs = self._succ[n]
+        if weight is None:
+            return sum(len(data) for data in nbrs.values())
+        # edge weighted graph - degree is sum of nbr edge weights
+        return sum(
+            d.get(weight, 1) for key_dict in nbrs.values() for d in key_dict.values()
+        )
+
+    def __iter__(self):
+        weight = self._weight
+        if weight is None:
+            for n in self._nodes:
+                nbrs = self._succ[n]
+                deg = sum(len(data) for data in nbrs.values())
+                yield (n, deg)
+        else:
+            for n in self._nodes:
+                nbrs = self._succ[n]
+                deg = sum(
+                    d.get(weight, 1)
+                    for key_dict in nbrs.values()
+                    for d in key_dict.values()
+                )
+                yield (n, deg)
+
+
+# EdgeDataViews
+class OutEdgeDataView:
+    """EdgeDataView for outward edges of DiGraph; See EdgeDataView"""
+
+    __slots__ = (
+        "_viewer",
+        "_nbunch",
+        "_data",
+        "_default",
+        "_adjdict",
+        "_nodes_nbrs",
+        "_report",
+    )
+
+    def __getstate__(self):
+        return {
+            "viewer": self._viewer,
+            "nbunch": self._nbunch,
+            "data": self._data,
+            "default": self._default,
+        }
+
+    def __setstate__(self, state):
+        self.__init__(**state)
+
+    def __init__(self, viewer, nbunch=None, data=False, *, default=None):
+        self._viewer = viewer
+        adjdict = self._adjdict = viewer._adjdict
+        if nbunch is None:
+            self._nodes_nbrs = adjdict.items
+        else:
+            # dict retains order of nodes but acts like a set
+            nbunch = dict.fromkeys(viewer._graph.nbunch_iter(nbunch))
+            self._nodes_nbrs = lambda: [(n, adjdict[n]) for n in nbunch]
+        self._nbunch = nbunch
+        self._data = data
+        self._default = default
+        # Set _report based on data and default
+        if data is True:
+            self._report = lambda n, nbr, dd: (n, nbr, dd)
+        elif data is False:
+            self._report = lambda n, nbr, dd: (n, nbr)
+        else:  # data is attribute name
+            self._report = (
+                lambda n, nbr, dd: (n, nbr, dd[data])
+                if data in dd
+                else (n, nbr, default)
+            )
+
+    def __len__(self):
+        return sum(len(nbrs) for n, nbrs in self._nodes_nbrs())
+
+    def __iter__(self):
+        return (
+            self._report(n, nbr, dd)
+            for n, nbrs in self._nodes_nbrs()
+            for nbr, dd in nbrs.items()
+        )
+
+    def __contains__(self, e):
+        u, v = e[:2]
+        if self._nbunch is not None and u not in self._nbunch:
+            return False  # this edge doesn't start in nbunch
+        try:
+            ddict = self._adjdict[u][v]
+        except KeyError:
+            return False
+        return e == self._report(u, v, ddict)
+
+    def __str__(self):
+        return str(list(self))
+
+    def __repr__(self):
+        return f"{self.__class__.__name__}({list(self)})"
+
+
+class EdgeDataView(OutEdgeDataView):
+    """A EdgeDataView class for edges of Graph
+
+    This view is primarily used to iterate over the edges reporting
+    edges as node-tuples with edge data optionally reported. The
+    argument `nbunch` allows restriction to edges incident to nodes
+    in that container/singleton. The default (nbunch=None)
+    reports all edges. The arguments `data` and `default` control
+    what edge data is reported. The default `data is False` reports
+    only node-tuples for each edge. If `data is True` the entire edge
+    data dict is returned. Otherwise `data` is assumed to hold the name
+    of the edge attribute to report with default `default` if  that
+    edge attribute is not present.
+
+    Parameters
+    ----------
+    nbunch : container of nodes, node or None (default None)
+    data : False, True or string (default False)
+    default : default value (default None)
+
+    Examples
+    --------
+    >>> G = nx.path_graph(3)
+    >>> G.add_edge(1, 2, foo="bar")
+    >>> list(G.edges(data="foo", default="biz"))
+    [(0, 1, 'biz'), (1, 2, 'bar')]
+    >>> assert (0, 1, "biz") in G.edges(data="foo", default="biz")
+    """
+
+    __slots__ = ()
+
+    def __len__(self):
+        return sum(1 for e in self)
+
+    def __iter__(self):
+        seen = {}
+        for n, nbrs in self._nodes_nbrs():
+            for nbr, dd in nbrs.items():
+                if nbr not in seen:
+                    yield self._report(n, nbr, dd)
+            seen[n] = 1
+        del seen
+
+    def __contains__(self, e):
+        u, v = e[:2]
+        if self._nbunch is not None and u not in self._nbunch and v not in self._nbunch:
+            return False  # this edge doesn't start and it doesn't end in nbunch
+        try:
+            ddict = self._adjdict[u][v]
+        except KeyError:
+            return False
+        return e == self._report(u, v, ddict)
+
+
+class InEdgeDataView(OutEdgeDataView):
+    """An EdgeDataView class for outward edges of DiGraph; See EdgeDataView"""
+
+    __slots__ = ()
+
+    def __iter__(self):
+        return (
+            self._report(nbr, n, dd)
+            for n, nbrs in self._nodes_nbrs()
+            for nbr, dd in nbrs.items()
+        )
+
+    def __contains__(self, e):
+        u, v = e[:2]
+        if self._nbunch is not None and v not in self._nbunch:
+            return False  # this edge doesn't end in nbunch
+        try:
+            ddict = self._adjdict[v][u]
+        except KeyError:
+            return False
+        return e == self._report(u, v, ddict)
+
+
+class OutMultiEdgeDataView(OutEdgeDataView):
+    """An EdgeDataView for outward edges of MultiDiGraph; See EdgeDataView"""
+
+    __slots__ = ("keys",)
+
+    def __getstate__(self):
+        return {
+            "viewer": self._viewer,
+            "nbunch": self._nbunch,
+            "keys": self.keys,
+            "data": self._data,
+            "default": self._default,
+        }
+
+    def __setstate__(self, state):
+        self.__init__(**state)
+
+    def __init__(self, viewer, nbunch=None, data=False, *, default=None, keys=False):
+        self._viewer = viewer
+        adjdict = self._adjdict = viewer._adjdict
+        self.keys = keys
+        if nbunch is None:
+            self._nodes_nbrs = adjdict.items
+        else:
+            # dict retains order of nodes but acts like a set
+            nbunch = dict.fromkeys(viewer._graph.nbunch_iter(nbunch))
+            self._nodes_nbrs = lambda: [(n, adjdict[n]) for n in nbunch]
+        self._nbunch = nbunch
+        self._data = data
+        self._default = default
+        # Set _report based on data and default
+        if data is True:
+            if keys is True:
+                self._report = lambda n, nbr, k, dd: (n, nbr, k, dd)
+            else:
+                self._report = lambda n, nbr, k, dd: (n, nbr, dd)
+        elif data is False:
+            if keys is True:
+                self._report = lambda n, nbr, k, dd: (n, nbr, k)
+            else:
+                self._report = lambda n, nbr, k, dd: (n, nbr)
+        else:  # data is attribute name
+            if keys is True:
+                self._report = (
+                    lambda n, nbr, k, dd: (n, nbr, k, dd[data])
+                    if data in dd
+                    else (n, nbr, k, default)
+                )
+            else:
+                self._report = (
+                    lambda n, nbr, k, dd: (n, nbr, dd[data])
+                    if data in dd
+                    else (n, nbr, default)
+                )
+
+    def __len__(self):
+        return sum(1 for e in self)
+
+    def __iter__(self):
+        return (
+            self._report(n, nbr, k, dd)
+            for n, nbrs in self._nodes_nbrs()
+            for nbr, kd in nbrs.items()
+            for k, dd in kd.items()
+        )
+
+    def __contains__(self, e):
+        u, v = e[:2]
+        if self._nbunch is not None and u not in self._nbunch:
+            return False  # this edge doesn't start in nbunch
+        try:
+            kdict = self._adjdict[u][v]
+        except KeyError:
+            return False
+        if self.keys is True:
+            k = e[2]
+            try:
+                dd = kdict[k]
+            except KeyError:
+                return False
+            return e == self._report(u, v, k, dd)
+        return any(e == self._report(u, v, k, dd) for k, dd in kdict.items())
+
+
+class MultiEdgeDataView(OutMultiEdgeDataView):
+    """An EdgeDataView class for edges of MultiGraph; See EdgeDataView"""
+
+    __slots__ = ()
+
+    def __iter__(self):
+        seen = {}
+        for n, nbrs in self._nodes_nbrs():
+            for nbr, kd in nbrs.items():
+                if nbr not in seen:
+                    for k, dd in kd.items():
+                        yield self._report(n, nbr, k, dd)
+            seen[n] = 1
+        del seen
+
+    def __contains__(self, e):
+        u, v = e[:2]
+        if self._nbunch is not None and u not in self._nbunch and v not in self._nbunch:
+            return False  # this edge doesn't start and doesn't end in nbunch
+        try:
+            kdict = self._adjdict[u][v]
+        except KeyError:
+            try:
+                kdict = self._adjdict[v][u]
+            except KeyError:
+                return False
+        if self.keys is True:
+            k = e[2]
+            try:
+                dd = kdict[k]
+            except KeyError:
+                return False
+            return e == self._report(u, v, k, dd)
+        return any(e == self._report(u, v, k, dd) for k, dd in kdict.items())
+
+
+class InMultiEdgeDataView(OutMultiEdgeDataView):
+    """An EdgeDataView for inward edges of MultiDiGraph; See EdgeDataView"""
+
+    __slots__ = ()
+
+    def __iter__(self):
+        return (
+            self._report(nbr, n, k, dd)
+            for n, nbrs in self._nodes_nbrs()
+            for nbr, kd in nbrs.items()
+            for k, dd in kd.items()
+        )
+
+    def __contains__(self, e):
+        u, v = e[:2]
+        if self._nbunch is not None and v not in self._nbunch:
+            return False  # this edge doesn't end in nbunch
+        try:
+            kdict = self._adjdict[v][u]
+        except KeyError:
+            return False
+        if self.keys is True:
+            k = e[2]
+            dd = kdict[k]
+            return e == self._report(u, v, k, dd)
+        return any(e == self._report(u, v, k, dd) for k, dd in kdict.items())
+
+
+# EdgeViews    have set operations and no data reported
+class OutEdgeView(Set, Mapping):
+    """A EdgeView class for outward edges of a DiGraph"""
+
+    __slots__ = ("_adjdict", "_graph", "_nodes_nbrs")
+
+    def __getstate__(self):
+        return {"_graph": self._graph, "_adjdict": self._adjdict}
+
+    def __setstate__(self, state):
+        self._graph = state["_graph"]
+        self._adjdict = state["_adjdict"]
+        self._nodes_nbrs = self._adjdict.items
+
+    @classmethod
+    def _from_iterable(cls, it):
+        return set(it)
+
+    dataview = OutEdgeDataView
+
+    def __init__(self, G):
+        self._graph = G
+        self._adjdict = G._succ if hasattr(G, "succ") else G._adj
+        self._nodes_nbrs = self._adjdict.items
+
+    # Set methods
+    def __len__(self):
+        return sum(len(nbrs) for n, nbrs in self._nodes_nbrs())
+
+    def __iter__(self):
+        for n, nbrs in self._nodes_nbrs():
+            for nbr in nbrs:
+                yield (n, nbr)
+
+    def __contains__(self, e):
+        try:
+            u, v = e
+            return v in self._adjdict[u]
+        except KeyError:
+            return False
+
+    # Mapping Methods
+    def __getitem__(self, e):
+        if isinstance(e, slice):
+            raise nx.NetworkXError(
+                f"{type(self).__name__} does not support slicing, "
+                f"try list(G.edges)[{e.start}:{e.stop}:{e.step}]"
+            )
+        u, v = e
+        try:
+            return self._adjdict[u][v]
+        except KeyError as ex:  # Customize msg to indicate exception origin
+            raise KeyError(f"The edge {e} is not in the graph.")
+
+    # EdgeDataView methods
+    def __call__(self, nbunch=None, data=False, *, default=None):
+        if nbunch is None and data is False:
+            return self
+        return self.dataview(self, nbunch, data, default=default)
+
+    def data(self, data=True, default=None, nbunch=None):
+        """
+        Return a read-only view of edge data.
+
+        Parameters
+        ----------
+        data : bool or edge attribute key
+            If ``data=True``, then the data view maps each edge to a dictionary
+            containing all of its attributes. If `data` is a key in the edge
+            dictionary, then the data view maps each edge to its value for
+            the keyed attribute. In this case, if the edge doesn't have the
+            attribute, the `default` value is returned.
+        default : object, default=None
+            The value used when an edge does not have a specific attribute
+        nbunch : container of nodes, optional (default=None)
+            Allows restriction to edges only involving certain nodes. All edges
+            are considered by default.
+
+        Returns
+        -------
+        dataview
+            Returns an `EdgeDataView` for undirected Graphs, `OutEdgeDataView`
+            for DiGraphs, `MultiEdgeDataView` for MultiGraphs and
+            `OutMultiEdgeDataView` for MultiDiGraphs.
+
+        Notes
+        -----
+        If ``data=False``, returns an `EdgeView` without any edge data.
+
+        See Also
+        --------
+        EdgeDataView
+        OutEdgeDataView
+        MultiEdgeDataView
+        OutMultiEdgeDataView
+
+        Examples
+        --------
+        >>> G = nx.Graph()
+        >>> G.add_edges_from(
+        ...     [
+        ...         (0, 1, {"dist": 3, "capacity": 20}),
+        ...         (1, 2, {"dist": 4}),
+        ...         (2, 0, {"dist": 5}),
+        ...     ]
+        ... )
+
+        Accessing edge data with ``data=True`` (the default) returns an
+        edge data view object listing each edge with all of its attributes:
+
+        >>> G.edges.data()
+        EdgeDataView([(0, 1, {'dist': 3, 'capacity': 20}), (0, 2, {'dist': 5}), (1, 2, {'dist': 4})])
+
+        If `data` represents a key in the edge attribute dict, a dataview listing
+        each edge with its value for that specific key is returned:
+
+        >>> G.edges.data("dist")
+        EdgeDataView([(0, 1, 3), (0, 2, 5), (1, 2, 4)])
+
+        `nbunch` can be used to limit the edges:
+
+        >>> G.edges.data("dist", nbunch=[0])
+        EdgeDataView([(0, 1, 3), (0, 2, 5)])
+
+        If a specific key is not found in an edge attribute dict, the value
+        specified by `default` is used:
+
+        >>> G.edges.data("capacity")
+        EdgeDataView([(0, 1, 20), (0, 2, None), (1, 2, None)])
+
+        Note that there is no check that the `data` key is present in any of
+        the edge attribute dictionaries:
+
+        >>> G.edges.data("speed")
+        EdgeDataView([(0, 1, None), (0, 2, None), (1, 2, None)])
+        """
+        if nbunch is None and data is False:
+            return self
+        return self.dataview(self, nbunch, data, default=default)
+
+    # String Methods
+    def __str__(self):
+        return str(list(self))
+
+    def __repr__(self):
+        return f"{self.__class__.__name__}({list(self)})"
+
+
+class EdgeView(OutEdgeView):
+    """A EdgeView class for edges of a Graph
+
+    This densely packed View allows iteration over edges, data lookup
+    like a dict and set operations on edges represented by node-tuples.
+    In addition, edge data can be controlled by calling this object
+    possibly creating an EdgeDataView. Typically edges are iterated over
+    and reported as `(u, v)` node tuples or `(u, v, key)` node/key tuples
+    for multigraphs. Those edge representations can also be using to
+    lookup the data dict for any edge. Set operations also are available
+    where those tuples are the elements of the set.
+    Calling this object with optional arguments `data`, `default` and `keys`
+    controls the form of the tuple (see EdgeDataView). Optional argument
+    `nbunch` allows restriction to edges only involving certain nodes.
+
+    If `data is False` (the default) then iterate over 2-tuples `(u, v)`.
+    If `data is True` iterate over 3-tuples `(u, v, datadict)`.
+    Otherwise iterate over `(u, v, datadict.get(data, default))`.
+    For Multigraphs, if `keys is True`, replace `u, v` with `u, v, key` above.
+
+    Parameters
+    ==========
+    graph : NetworkX graph-like class
+    nbunch : (default= all nodes in graph) only report edges with these nodes
+    keys : (only for MultiGraph. default=False) report edge key in tuple
+    data : bool or string (default=False) see above
+    default : object (default=None)
+
+    Examples
+    ========
+    >>> G = nx.path_graph(4)
+    >>> EV = G.edges()
+    >>> (2, 3) in EV
+    True
+    >>> for u, v in EV:
+    ...     print((u, v))
+    (0, 1)
+    (1, 2)
+    (2, 3)
+    >>> assert EV & {(1, 2), (3, 4)} == {(1, 2)}
+
+    >>> EVdata = G.edges(data="color", default="aqua")
+    >>> G.add_edge(2, 3, color="blue")
+    >>> assert (2, 3, "blue") in EVdata
+    >>> for u, v, c in EVdata:
+    ...     print(f"({u}, {v}) has color: {c}")
+    (0, 1) has color: aqua
+    (1, 2) has color: aqua
+    (2, 3) has color: blue
+
+    >>> EVnbunch = G.edges(nbunch=2)
+    >>> assert (2, 3) in EVnbunch
+    >>> assert (0, 1) not in EVnbunch
+    >>> for u, v in EVnbunch:
+    ...     assert u == 2 or v == 2
+
+    >>> MG = nx.path_graph(4, create_using=nx.MultiGraph)
+    >>> EVmulti = MG.edges(keys=True)
+    >>> (2, 3, 0) in EVmulti
+    True
+    >>> (2, 3) in EVmulti  # 2-tuples work even when keys is True
+    True
+    >>> key = MG.add_edge(2, 3)
+    >>> for u, v, k in EVmulti:
+    ...     print((u, v, k))
+    (0, 1, 0)
+    (1, 2, 0)
+    (2, 3, 0)
+    (2, 3, 1)
+    """
+
+    __slots__ = ()
+
+    dataview = EdgeDataView
+
+    def __len__(self):
+        num_nbrs = (len(nbrs) + (n in nbrs) for n, nbrs in self._nodes_nbrs())
+        return sum(num_nbrs) // 2
+
+    def __iter__(self):
+        seen = {}
+        for n, nbrs in self._nodes_nbrs():
+            for nbr in list(nbrs):
+                if nbr not in seen:
+                    yield (n, nbr)
+            seen[n] = 1
+        del seen
+
+    def __contains__(self, e):
+        try:
+            u, v = e[:2]
+            return v in self._adjdict[u] or u in self._adjdict[v]
+        except (KeyError, ValueError):
+            return False
+
+
+class InEdgeView(OutEdgeView):
+    """A EdgeView class for inward edges of a DiGraph"""
+
+    __slots__ = ()
+
+    def __setstate__(self, state):
+        self._graph = state["_graph"]
+        self._adjdict = state["_adjdict"]
+        self._nodes_nbrs = self._adjdict.items
+
+    dataview = InEdgeDataView
+
+    def __init__(self, G):
+        self._graph = G
+        self._adjdict = G._pred if hasattr(G, "pred") else G._adj
+        self._nodes_nbrs = self._adjdict.items
+
+    def __iter__(self):
+        for n, nbrs in self._nodes_nbrs():
+            for nbr in nbrs:
+                yield (nbr, n)
+
+    def __contains__(self, e):
+        try:
+            u, v = e
+            return u in self._adjdict[v]
+        except KeyError:
+            return False
+
+    def __getitem__(self, e):
+        if isinstance(e, slice):
+            raise nx.NetworkXError(
+                f"{type(self).__name__} does not support slicing, "
+                f"try list(G.in_edges)[{e.start}:{e.stop}:{e.step}]"
+            )
+        u, v = e
+        return self._adjdict[v][u]
+
+
+class OutMultiEdgeView(OutEdgeView):
+    """A EdgeView class for outward edges of a MultiDiGraph"""
+
+    __slots__ = ()
+
+    dataview = OutMultiEdgeDataView
+
+    def __len__(self):
+        return sum(
+            len(kdict) for n, nbrs in self._nodes_nbrs() for nbr, kdict in nbrs.items()
+        )
+
+    def __iter__(self):
+        for n, nbrs in self._nodes_nbrs():
+            for nbr, kdict in nbrs.items():
+                for key in kdict:
+                    yield (n, nbr, key)
+
+    def __contains__(self, e):
+        N = len(e)
+        if N == 3:
+            u, v, k = e
+        elif N == 2:
+            u, v = e
+            k = 0
+        else:
+            raise ValueError("MultiEdge must have length 2 or 3")
+        try:
+            return k in self._adjdict[u][v]
+        except KeyError:
+            return False
+
+    def __getitem__(self, e):
+        if isinstance(e, slice):
+            raise nx.NetworkXError(
+                f"{type(self).__name__} does not support slicing, "
+                f"try list(G.edges)[{e.start}:{e.stop}:{e.step}]"
+            )
+        u, v, k = e
+        return self._adjdict[u][v][k]
+
+    def __call__(self, nbunch=None, data=False, *, default=None, keys=False):
+        if nbunch is None and data is False and keys is True:
+            return self
+        return self.dataview(self, nbunch, data, default=default, keys=keys)
+
+    def data(self, data=True, default=None, nbunch=None, keys=False):
+        if nbunch is None and data is False and keys is True:
+            return self
+        return self.dataview(self, nbunch, data, default=default, keys=keys)
+
+
+class MultiEdgeView(OutMultiEdgeView):
+    """A EdgeView class for edges of a MultiGraph"""
+
+    __slots__ = ()
+
+    dataview = MultiEdgeDataView
+
+    def __len__(self):
+        return sum(1 for e in self)
+
+    def __iter__(self):
+        seen = {}
+        for n, nbrs in self._nodes_nbrs():
+            for nbr, kd in nbrs.items():
+                if nbr not in seen:
+                    for k, dd in kd.items():
+                        yield (n, nbr, k)
+            seen[n] = 1
+        del seen
+
+
+class InMultiEdgeView(OutMultiEdgeView):
+    """A EdgeView class for inward edges of a MultiDiGraph"""
+
+    __slots__ = ()
+
+    def __setstate__(self, state):
+        self._graph = state["_graph"]
+        self._adjdict = state["_adjdict"]
+        self._nodes_nbrs = self._adjdict.items
+
+    dataview = InMultiEdgeDataView
+
+    def __init__(self, G):
+        self._graph = G
+        self._adjdict = G._pred if hasattr(G, "pred") else G._adj
+        self._nodes_nbrs = self._adjdict.items
+
+    def __iter__(self):
+        for n, nbrs in self._nodes_nbrs():
+            for nbr, kdict in nbrs.items():
+                for key in kdict:
+                    yield (nbr, n, key)
+
+    def __contains__(self, e):
+        N = len(e)
+        if N == 3:
+            u, v, k = e
+        elif N == 2:
+            u, v = e
+            k = 0
+        else:
+            raise ValueError("MultiEdge must have length 2 or 3")
+        try:
+            return k in self._adjdict[v][u]
+        except KeyError:
+            return False
+
+    def __getitem__(self, e):
+        if isinstance(e, slice):
+            raise nx.NetworkXError(
+                f"{type(self).__name__} does not support slicing, "
+                f"try list(G.in_edges)[{e.start}:{e.stop}:{e.step}]"
+            )
+        u, v, k = e
+        return self._adjdict[v][u][k]

venv/lib/python3.10/site-packages/networkx/classes/tests/dispatch_interface.py

@@ -0,0 +1,194 @@
+# This file contains utilities for testing the dispatching feature
+
+# A full test of all dispatchable algorithms is performed by
+# modifying the pytest invocation and setting an environment variable
+# NETWORKX_TEST_BACKEND=nx-loopback pytest
+# This is comprehensive, but only tests the `test_override_dispatch`
+# function in networkx.classes.backends.
+
+# To test the `_dispatchable` function directly, several tests scattered throughout
+# NetworkX have been augmented to test normal and dispatch mode.
+# Searching for `dispatch_interface` should locate the specific tests.
+
+import networkx as nx
+from networkx import DiGraph, Graph, MultiDiGraph, MultiGraph, PlanarEmbedding
+from networkx.classes.reportviews import NodeView
+
+
+class LoopbackGraph(Graph):
+    __networkx_backend__ = "nx-loopback"
+
+
+class LoopbackDiGraph(DiGraph):
+    __networkx_backend__ = "nx-loopback"
+
+
+class LoopbackMultiGraph(MultiGraph):
+    __networkx_backend__ = "nx-loopback"
+
+
+class LoopbackMultiDiGraph(MultiDiGraph):
+    __networkx_backend__ = "nx-loopback"
+
+
+class LoopbackPlanarEmbedding(PlanarEmbedding):
+    __networkx_backend__ = "nx-loopback"
+
+
+def convert(graph):
+    if isinstance(graph, PlanarEmbedding):
+        return LoopbackPlanarEmbedding(graph)
+    if isinstance(graph, MultiDiGraph):
+        return LoopbackMultiDiGraph(graph)
+    if isinstance(graph, MultiGraph):
+        return LoopbackMultiGraph(graph)
+    if isinstance(graph, DiGraph):
+        return LoopbackDiGraph(graph)
+    if isinstance(graph, Graph):
+        return LoopbackGraph(graph)
+    raise TypeError(f"Unsupported type of graph: {type(graph)}")
+
+
+class LoopbackDispatcher:
+    def __getattr__(self, item):
+        try:
+            return nx.utils.backends._registered_algorithms[item].orig_func
+        except KeyError:
+            raise AttributeError(item) from None
+
+    @staticmethod
+    def convert_from_nx(
+        graph,
+        *,
+        edge_attrs=None,
+        node_attrs=None,
+        preserve_edge_attrs=None,
+        preserve_node_attrs=None,
+        preserve_graph_attrs=None,
+        name=None,
+        graph_name=None,
+    ):
+        if name in {
+            # Raise if input graph changes
+            "lexicographical_topological_sort",
+            "topological_generations",
+            "topological_sort",
+            # Sensitive tests (iteration order matters)
+            "dfs_labeled_edges",
+        }:
+            return graph
+        if isinstance(graph, NodeView):
+            # Convert to a Graph with only nodes (no edges)
+            new_graph = Graph()
+            new_graph.add_nodes_from(graph.items())
+            graph = new_graph
+            G = LoopbackGraph()
+        elif not isinstance(graph, Graph):
+            raise TypeError(
+                f"Bad type for graph argument {graph_name} in {name}: {type(graph)}"
+            )
+        elif graph.__class__ in {Graph, LoopbackGraph}:
+            G = LoopbackGraph()
+        elif graph.__class__ in {DiGraph, LoopbackDiGraph}:
+            G = LoopbackDiGraph()
+        elif graph.__class__ in {MultiGraph, LoopbackMultiGraph}:
+            G = LoopbackMultiGraph()
+        elif graph.__class__ in {MultiDiGraph, LoopbackMultiDiGraph}:
+            G = LoopbackMultiDiGraph()
+        elif graph.__class__ in {PlanarEmbedding, LoopbackPlanarEmbedding}:
+            G = LoopbackDiGraph()  # or LoopbackPlanarEmbedding
+        else:
+            # It would be nice to be able to convert _AntiGraph to a regular Graph
+            # nx.algorithms.approximation.kcomponents._AntiGraph
+            # nx.algorithms.tree.branchings.MultiDiGraph_EdgeKey
+            # nx.classes.tests.test_multidigraph.MultiDiGraphSubClass
+            # nx.classes.tests.test_multigraph.MultiGraphSubClass
+            G = graph.__class__()
+
+        if preserve_graph_attrs:
+            G.graph.update(graph.graph)
+
+        if preserve_node_attrs:
+            G.add_nodes_from(graph.nodes(data=True))
+        elif node_attrs:
+            G.add_nodes_from(
+                (
+                    node,
+                    {
+                        k: datadict.get(k, default)
+                        for k, default in node_attrs.items()
+                        if default is not None or k in datadict
+                    },
+                )
+                for node, datadict in graph.nodes(data=True)
+            )
+        else:
+            G.add_nodes_from(graph)
+
+        if graph.is_multigraph():
+            if preserve_edge_attrs:
+                G.add_edges_from(
+                    (u, v, key, datadict)
+                    for u, nbrs in graph._adj.items()
+                    for v, keydict in nbrs.items()
+                    for key, datadict in keydict.items()
+                )
+            elif edge_attrs:
+                G.add_edges_from(
+                    (
+                        u,
+                        v,
+                        key,
+                        {
+                            k: datadict.get(k, default)
+                            for k, default in edge_attrs.items()
+                            if default is not None or k in datadict
+                        },
+                    )
+                    for u, nbrs in graph._adj.items()
+                    for v, keydict in nbrs.items()
+                    for key, datadict in keydict.items()
+                )
+            else:
+                G.add_edges_from(
+                    (u, v, key, {})
+                    for u, nbrs in graph._adj.items()
+                    for v, keydict in nbrs.items()
+                    for key, datadict in keydict.items()
+                )
+        elif preserve_edge_attrs:
+            G.add_edges_from(graph.edges(data=True))
+        elif edge_attrs:
+            G.add_edges_from(
+                (
+                    u,
+                    v,
+                    {
+                        k: datadict.get(k, default)
+                        for k, default in edge_attrs.items()
+                        if default is not None or k in datadict
+                    },
+                )
+                for u, v, datadict in graph.edges(data=True)
+            )
+        else:
+            G.add_edges_from(graph.edges)
+        return G
+
+    @staticmethod
+    def convert_to_nx(obj, *, name=None):
+        return obj
+
+    @staticmethod
+    def on_start_tests(items):
+        # Verify that items can be xfailed
+        for item in items:
+            assert hasattr(item, "add_marker")
+
+    def can_run(self, name, args, kwargs):
+        # It is unnecessary to define this function if algorithms are fully supported.
+        # We include it for illustration purposes.
+        return hasattr(self, name)
+
+
+dispatcher = LoopbackDispatcher()

venv/lib/python3.10/site-packages/networkx/classes/tests/historical_tests.py

@@ -0,0 +1,474 @@
+"""Original NetworkX graph tests"""
+import pytest
+
+import networkx as nx
+from networkx import convert_node_labels_to_integers as cnlti
+from networkx.utils import edges_equal, nodes_equal
+
+
+class HistoricalTests:
+    @classmethod
+    def setup_class(cls):
+        cls.null = nx.null_graph()
+        cls.P1 = cnlti(nx.path_graph(1), first_label=1)
+        cls.P3 = cnlti(nx.path_graph(3), first_label=1)
+        cls.P10 = cnlti(nx.path_graph(10), first_label=1)
+        cls.K1 = cnlti(nx.complete_graph(1), first_label=1)
+        cls.K3 = cnlti(nx.complete_graph(3), first_label=1)
+        cls.K4 = cnlti(nx.complete_graph(4), first_label=1)
+        cls.K5 = cnlti(nx.complete_graph(5), first_label=1)
+        cls.K10 = cnlti(nx.complete_graph(10), first_label=1)
+        cls.G = nx.Graph
+
+    def test_name(self):
+        G = self.G(name="test")
+        assert G.name == "test"
+        H = self.G()
+        assert H.name == ""
+
+    # Nodes
+
+    def test_add_remove_node(self):
+        G = self.G()
+        G.add_node("A")
+        assert G.has_node("A")
+        G.remove_node("A")
+        assert not G.has_node("A")
+
+    def test_nonhashable_node(self):
+        # Test if a non-hashable object is in the Graph.  A python dict will
+        # raise a TypeError, but for a Graph class a simple  False should be
+        # returned (see Graph __contains__). If it cannot be a node then it is
+        # not a node.
+        G = self.G()
+        assert not G.has_node(["A"])
+        assert not G.has_node({"A": 1})
+
+    def test_add_nodes_from(self):
+        G = self.G()
+        G.add_nodes_from(list("ABCDEFGHIJKL"))
+        assert G.has_node("L")
+        G.remove_nodes_from(["H", "I", "J", "K", "L"])
+        G.add_nodes_from([1, 2, 3, 4])
+        assert sorted(G.nodes(), key=str) == [
+            1,
+            2,
+            3,
+            4,
+            "A",
+            "B",
+            "C",
+            "D",
+            "E",
+            "F",
+            "G",
+        ]
+        # test __iter__
+        assert sorted(G, key=str) == [1, 2, 3, 4, "A", "B", "C", "D", "E", "F", "G"]
+
+    def test_contains(self):
+        G = self.G()
+        G.add_node("A")
+        assert "A" in G
+        assert [] not in G  # never raise a Key or TypeError in this test
+        assert {1: 1} not in G
+
+    def test_add_remove(self):
+        # Test add_node and remove_node acting for various nbunch
+        G = self.G()
+        G.add_node("m")
+        assert G.has_node("m")
+        G.add_node("m")  # no complaints
+        pytest.raises(nx.NetworkXError, G.remove_node, "j")
+        G.remove_node("m")
+        assert list(G) == []
+
+    def test_nbunch_is_list(self):
+        G = self.G()
+        G.add_nodes_from(list("ABCD"))
+        G.add_nodes_from(self.P3)  # add nbunch of nodes (nbunch=Graph)
+        assert sorted(G.nodes(), key=str) == [1, 2, 3, "A", "B", "C", "D"]
+        G.remove_nodes_from(self.P3)  # remove nbunch of nodes (nbunch=Graph)
+        assert sorted(G.nodes(), key=str) == ["A", "B", "C", "D"]
+
+    def test_nbunch_is_set(self):
+        G = self.G()
+        nbunch = set("ABCDEFGHIJKL")
+        G.add_nodes_from(nbunch)
+        assert G.has_node("L")
+
+    def test_nbunch_dict(self):
+        # nbunch is a dict with nodes as keys
+        G = self.G()
+        nbunch = set("ABCDEFGHIJKL")
+        G.add_nodes_from(nbunch)
+        nbunch = {"I": "foo", "J": 2, "K": True, "L": "spam"}
+        G.remove_nodes_from(nbunch)
+        assert sorted(G.nodes(), key=str), ["A", "B", "C", "D", "E", "F", "G", "H"]
+
+    def test_nbunch_iterator(self):
+        G = self.G()
+        G.add_nodes_from(["A", "B", "C", "D", "E", "F", "G", "H"])
+        n_iter = self.P3.nodes()
+        G.add_nodes_from(n_iter)
+        assert sorted(G.nodes(), key=str) == [
+            1,
+            2,
+            3,
+            "A",
+            "B",
+            "C",
+            "D",
+            "E",
+            "F",
+            "G",
+            "H",
+        ]
+        n_iter = self.P3.nodes()  # rebuild same iterator
+        G.remove_nodes_from(n_iter)  # remove nbunch of nodes (nbunch=iterator)
+        assert sorted(G.nodes(), key=str) == ["A", "B", "C", "D", "E", "F", "G", "H"]
+
+    def test_nbunch_graph(self):
+        G = self.G()
+        G.add_nodes_from(["A", "B", "C", "D", "E", "F", "G", "H"])
+        nbunch = self.K3
+        G.add_nodes_from(nbunch)
+        assert sorted(G.nodes(), key=str), [
+            1,
+            2,
+            3,
+            "A",
+            "B",
+            "C",
+            "D",
+            "E",
+            "F",
+            "G",
+            "H",
+        ]
+
+    # Edges
+
+    def test_add_edge(self):
+        G = self.G()
+        pytest.raises(TypeError, G.add_edge, "A")
+
+        G.add_edge("A", "B")  # testing add_edge()
+        G.add_edge("A", "B")  # should fail silently
+        assert G.has_edge("A", "B")
+        assert not G.has_edge("A", "C")
+        assert G.has_edge(*("A", "B"))
+        if G.is_directed():
+            assert not G.has_edge("B", "A")
+        else:
+            # G is undirected, so B->A is an edge
+            assert G.has_edge("B", "A")
+
+        G.add_edge("A", "C")  # test directedness
+        G.add_edge("C", "A")
+        G.remove_edge("C", "A")
+        if G.is_directed():
+            assert G.has_edge("A", "C")
+        else:
+            assert not G.has_edge("A", "C")
+        assert not G.has_edge("C", "A")
+
+    def test_self_loop(self):
+        G = self.G()
+        G.add_edge("A", "A")  # test self loops
+        assert G.has_edge("A", "A")
+        G.remove_edge("A", "A")
+        G.add_edge("X", "X")
+        assert G.has_node("X")
+        G.remove_node("X")
+        G.add_edge("A", "Z")  # should add the node silently
+        assert G.has_node("Z")
+
+    def test_add_edges_from(self):
+        G = self.G()
+        G.add_edges_from([("B", "C")])  # test add_edges_from()
+        assert G.has_edge("B", "C")
+        if G.is_directed():
+            assert not G.has_edge("C", "B")
+        else:
+            assert G.has_edge("C", "B")  # undirected
+
+        G.add_edges_from([("D", "F"), ("B", "D")])
+        assert G.has_edge("D", "F")
+        assert G.has_edge("B", "D")
+
+        if G.is_directed():
+            assert not G.has_edge("D", "B")
+        else:
+            assert G.has_edge("D", "B")  # undirected
+
+    def test_add_edges_from2(self):
+        G = self.G()
+        # after failing silently, should add 2nd edge
+        G.add_edges_from([tuple("IJ"), list("KK"), tuple("JK")])
+        assert G.has_edge(*("I", "J"))
+        assert G.has_edge(*("K", "K"))
+        assert G.has_edge(*("J", "K"))
+        if G.is_directed():
+            assert not G.has_edge(*("K", "J"))
+        else:
+            assert G.has_edge(*("K", "J"))
+
+    def test_add_edges_from3(self):
+        G = self.G()
+        G.add_edges_from(zip(list("ACD"), list("CDE")))
+        assert G.has_edge("D", "E")
+        assert not G.has_edge("E", "C")
+
+    def test_remove_edge(self):
+        G = self.G()
+        G.add_nodes_from([1, 2, 3, "A", "B", "C", "D", "E", "F", "G", "H"])
+
+        G.add_edges_from(zip(list("MNOP"), list("NOPM")))
+        assert G.has_edge("O", "P")
+        assert G.has_edge("P", "M")
+        G.remove_node("P")  # tests remove_node()'s handling of edges.
+        assert not G.has_edge("P", "M")
+        pytest.raises(TypeError, G.remove_edge, "M")
+
+        G.add_edge("N", "M")
+        assert G.has_edge("M", "N")
+        G.remove_edge("M", "N")
+        assert not G.has_edge("M", "N")
+
+        # self loop fails silently
+        G.remove_edges_from([list("HI"), list("DF"), tuple("KK"), tuple("JK")])
+        assert not G.has_edge("H", "I")
+        assert not G.has_edge("J", "K")
+        G.remove_edges_from([list("IJ"), list("KK"), list("JK")])
+        assert not G.has_edge("I", "J")
+        G.remove_nodes_from(set("ZEFHIMNO"))
+        G.add_edge("J", "K")
+
+    def test_edges_nbunch(self):
+        # Test G.edges(nbunch) with various forms of nbunch
+        G = self.G()
+        G.add_edges_from([("A", "B"), ("A", "C"), ("B", "D"), ("C", "B"), ("C", "D")])
+        # node not in nbunch should be quietly ignored
+        pytest.raises(nx.NetworkXError, G.edges, 6)
+        assert list(G.edges("Z")) == []  # iterable non-node
+        # nbunch can be an empty list
+        assert list(G.edges([])) == []
+        if G.is_directed():
+            elist = [("A", "B"), ("A", "C"), ("B", "D")]
+        else:
+            elist = [("A", "B"), ("A", "C"), ("B", "C"), ("B", "D")]
+        # nbunch can be a list
+        assert edges_equal(list(G.edges(["A", "B"])), elist)
+        # nbunch can be a set
+        assert edges_equal(G.edges({"A", "B"}), elist)
+        # nbunch can be a graph
+        G1 = self.G()
+        G1.add_nodes_from("AB")
+        assert edges_equal(G.edges(G1), elist)
+        # nbunch can be a dict with nodes as keys
+        ndict = {"A": "thing1", "B": "thing2"}
+        assert edges_equal(G.edges(ndict), elist)
+        # nbunch can be a single node
+        assert edges_equal(list(G.edges("A")), [("A", "B"), ("A", "C")])
+        assert nodes_equal(sorted(G), ["A", "B", "C", "D"])
+
+        # nbunch can be nothing (whole graph)
+        assert edges_equal(
+            list(G.edges()),
+            [("A", "B"), ("A", "C"), ("B", "D"), ("C", "B"), ("C", "D")],
+        )
+
+    def test_degree(self):
+        G = self.G()
+        G.add_edges_from([("A", "B"), ("A", "C"), ("B", "D"), ("C", "B"), ("C", "D")])
+        assert G.degree("A") == 2
+
+        # degree of single node in iterable container must return dict
+        assert list(G.degree(["A"])) == [("A", 2)]
+        assert sorted(d for n, d in G.degree(["A", "B"])) == [2, 3]
+        assert sorted(d for n, d in G.degree()) == [2, 2, 3, 3]
+
+    def test_degree2(self):
+        H = self.G()
+        H.add_edges_from([(1, 24), (1, 2)])
+        assert sorted(d for n, d in H.degree([1, 24])) == [1, 2]
+
+    def test_degree_graph(self):
+        P3 = nx.path_graph(3)
+        P5 = nx.path_graph(5)
+        # silently ignore nodes not in P3
+        assert dict(d for n, d in P3.degree(["A", "B"])) == {}
+        # nbunch can be a graph
+        assert sorted(d for n, d in P5.degree(P3)) == [1, 2, 2]
+        # nbunch can be a graph that's way too big
+        assert sorted(d for n, d in P3.degree(P5)) == [1, 1, 2]
+        assert list(P5.degree([])) == []
+        assert dict(P5.degree([])) == {}
+
+    def test_null(self):
+        null = nx.null_graph()
+        assert list(null.degree()) == []
+        assert dict(null.degree()) == {}
+
+    def test_order_size(self):
+        G = self.G()
+        G.add_edges_from([("A", "B"), ("A", "C"), ("B", "D"), ("C", "B"), ("C", "D")])
+        assert G.order() == 4
+        assert G.size() == 5
+        assert G.number_of_edges() == 5
+        assert G.number_of_edges("A", "B") == 1
+        assert G.number_of_edges("A", "D") == 0
+
+    def test_copy(self):
+        G = self.G()
+        H = G.copy()  # copy
+        assert H.adj == G.adj
+        assert H.name == G.name
+        assert H is not G
+
+    def test_subgraph(self):
+        G = self.G()
+        G.add_edges_from([("A", "B"), ("A", "C"), ("B", "D"), ("C", "B"), ("C", "D")])
+        SG = G.subgraph(["A", "B", "D"])
+        assert nodes_equal(list(SG), ["A", "B", "D"])
+        assert edges_equal(list(SG.edges()), [("A", "B"), ("B", "D")])
+
+    def test_to_directed(self):
+        G = self.G()
+        if not G.is_directed():
+            G.add_edges_from(
+                [("A", "B"), ("A", "C"), ("B", "D"), ("C", "B"), ("C", "D")]
+            )
+
+            DG = G.to_directed()
+            assert DG is not G  # directed copy or copy
+
+            assert DG.is_directed()
+            assert DG.name == G.name
+            assert DG.adj == G.adj
+            assert sorted(DG.out_edges(list("AB"))) == [
+                ("A", "B"),
+                ("A", "C"),
+                ("B", "A"),
+                ("B", "C"),
+                ("B", "D"),
+            ]
+            DG.remove_edge("A", "B")
+            assert DG.has_edge("B", "A")  # this removes B-A but not  A-B
+            assert not DG.has_edge("A", "B")
+
+    def test_to_undirected(self):
+        G = self.G()
+        if G.is_directed():
+            G.add_edges_from(
+                [("A", "B"), ("A", "C"), ("B", "D"), ("C", "B"), ("C", "D")]
+            )
+            UG = G.to_undirected()  # to_undirected
+            assert UG is not G
+            assert not UG.is_directed()
+            assert G.is_directed()
+            assert UG.name == G.name
+            assert UG.adj != G.adj
+            assert sorted(UG.edges(list("AB"))) == [
+                ("A", "B"),
+                ("A", "C"),
+                ("B", "C"),
+                ("B", "D"),
+            ]
+            assert sorted(UG.edges(["A", "B"])) == [
+                ("A", "B"),
+                ("A", "C"),
+                ("B", "C"),
+                ("B", "D"),
+            ]
+            UG.remove_edge("A", "B")
+            assert not UG.has_edge("B", "A")
+            assert not UG.has_edge("A", "B")
+
+    def test_neighbors(self):
+        G = self.G()
+        G.add_edges_from([("A", "B"), ("A", "C"), ("B", "D"), ("C", "B"), ("C", "D")])
+        G.add_nodes_from("GJK")
+        assert sorted(G["A"]) == ["B", "C"]
+        assert sorted(G.neighbors("A")) == ["B", "C"]
+        assert sorted(G.neighbors("A")) == ["B", "C"]
+        assert sorted(G.neighbors("G")) == []
+        pytest.raises(nx.NetworkXError, G.neighbors, "j")
+
+    def test_iterators(self):
+        G = self.G()
+        G.add_edges_from([("A", "B"), ("A", "C"), ("B", "D"), ("C", "B"), ("C", "D")])
+        G.add_nodes_from("GJK")
+        assert sorted(G.nodes()) == ["A", "B", "C", "D", "G", "J", "K"]
+        assert edges_equal(
+            G.edges(), [("A", "B"), ("A", "C"), ("B", "D"), ("C", "B"), ("C", "D")]
+        )
+
+        assert sorted(v for k, v in G.degree()) == [0, 0, 0, 2, 2, 3, 3]
+        assert sorted(G.degree(), key=str) == [
+            ("A", 2),
+            ("B", 3),
+            ("C", 3),
+            ("D", 2),
+            ("G", 0),
+            ("J", 0),
+            ("K", 0),
+        ]
+        assert sorted(G.neighbors("A")) == ["B", "C"]
+        pytest.raises(nx.NetworkXError, G.neighbors, "X")
+        G.clear()
+        assert nx.number_of_nodes(G) == 0
+        assert nx.number_of_edges(G) == 0
+
+    def test_null_subgraph(self):
+        # Subgraph of a null graph is a null graph
+        nullgraph = nx.null_graph()
+        G = nx.null_graph()
+        H = G.subgraph([])
+        assert nx.is_isomorphic(H, nullgraph)
+
+    def test_empty_subgraph(self):
+        # Subgraph of an empty graph is an empty graph. test 1
+        nullgraph = nx.null_graph()
+        E5 = nx.empty_graph(5)
+        E10 = nx.empty_graph(10)
+        H = E10.subgraph([])
+        assert nx.is_isomorphic(H, nullgraph)
+        H = E10.subgraph([1, 2, 3, 4, 5])
+        assert nx.is_isomorphic(H, E5)
+
+    def test_complete_subgraph(self):
+        # Subgraph of a complete graph is a complete graph
+        K1 = nx.complete_graph(1)
+        K3 = nx.complete_graph(3)
+        K5 = nx.complete_graph(5)
+        H = K5.subgraph([1, 2, 3])
+        assert nx.is_isomorphic(H, K3)
+
+    def test_subgraph_nbunch(self):
+        nullgraph = nx.null_graph()
+        K1 = nx.complete_graph(1)
+        K3 = nx.complete_graph(3)
+        K5 = nx.complete_graph(5)
+        # Test G.subgraph(nbunch), where nbunch is a single node
+        H = K5.subgraph(1)
+        assert nx.is_isomorphic(H, K1)
+        # Test G.subgraph(nbunch), where nbunch is a set
+        H = K5.subgraph({1})
+        assert nx.is_isomorphic(H, K1)
+        # Test G.subgraph(nbunch), where nbunch is an iterator
+        H = K5.subgraph(iter(K3))
+        assert nx.is_isomorphic(H, K3)
+        # Test G.subgraph(nbunch), where nbunch is another graph
+        H = K5.subgraph(K3)
+        assert nx.is_isomorphic(H, K3)
+        H = K5.subgraph([9])
+        assert nx.is_isomorphic(H, nullgraph)
+
+    def test_node_tuple_issue(self):
+        H = self.G()
+        # Test error handling of tuple as a node
+        pytest.raises(nx.NetworkXError, H.remove_node, (1, 2))
+        H.remove_nodes_from([(1, 2)])  # no error
+        pytest.raises(nx.NetworkXError, H.neighbors, (1, 2))

venv/lib/python3.10/site-packages/networkx/classes/tests/test_digraph.py

@@ -0,0 +1,331 @@
+import pytest
+
+import networkx as nx
+from networkx.utils import nodes_equal
+
+from .test_graph import BaseAttrGraphTester, BaseGraphTester
+from .test_graph import TestEdgeSubgraph as _TestGraphEdgeSubgraph
+from .test_graph import TestGraph as _TestGraph
+
+
+class BaseDiGraphTester(BaseGraphTester):
+    def test_has_successor(self):
+        G = self.K3
+        assert G.has_successor(0, 1)
+        assert not G.has_successor(0, -1)
+
+    def test_successors(self):
+        G = self.K3
+        assert sorted(G.successors(0)) == [1, 2]
+        with pytest.raises(nx.NetworkXError):
+            G.successors(-1)
+
+    def test_has_predecessor(self):
+        G = self.K3
+        assert G.has_predecessor(0, 1)
+        assert not G.has_predecessor(0, -1)
+
+    def test_predecessors(self):
+        G = self.K3
+        assert sorted(G.predecessors(0)) == [1, 2]
+        with pytest.raises(nx.NetworkXError):
+            G.predecessors(-1)
+
+    def test_edges(self):
+        G = self.K3
+        assert sorted(G.edges()) == [(0, 1), (0, 2), (1, 0), (1, 2), (2, 0), (2, 1)]
+        assert sorted(G.edges(0)) == [(0, 1), (0, 2)]
+        assert sorted(G.edges([0, 1])) == [(0, 1), (0, 2), (1, 0), (1, 2)]
+        with pytest.raises(nx.NetworkXError):
+            G.edges(-1)
+
+    def test_out_edges(self):
+        G = self.K3
+        assert sorted(G.out_edges()) == [(0, 1), (0, 2), (1, 0), (1, 2), (2, 0), (2, 1)]
+        assert sorted(G.out_edges(0)) == [(0, 1), (0, 2)]
+        with pytest.raises(nx.NetworkXError):
+            G.out_edges(-1)
+
+    def test_out_edges_dir(self):
+        G = self.P3
+        assert sorted(G.out_edges()) == [(0, 1), (1, 2)]
+        assert sorted(G.out_edges(0)) == [(0, 1)]
+        assert sorted(G.out_edges(2)) == []
+
+    def test_out_edges_data(self):
+        G = nx.DiGraph([(0, 1, {"data": 0}), (1, 0, {})])
+        assert sorted(G.out_edges(data=True)) == [(0, 1, {"data": 0}), (1, 0, {})]
+        assert sorted(G.out_edges(0, data=True)) == [(0, 1, {"data": 0})]
+        assert sorted(G.out_edges(data="data")) == [(0, 1, 0), (1, 0, None)]
+        assert sorted(G.out_edges(0, data="data")) == [(0, 1, 0)]
+
+    def test_in_edges_dir(self):
+        G = self.P3
+        assert sorted(G.in_edges()) == [(0, 1), (1, 2)]
+        assert sorted(G.in_edges(0)) == []
+        assert sorted(G.in_edges(2)) == [(1, 2)]
+
+    def test_in_edges_data(self):
+        G = nx.DiGraph([(0, 1, {"data": 0}), (1, 0, {})])
+        assert sorted(G.in_edges(data=True)) == [(0, 1, {"data": 0}), (1, 0, {})]
+        assert sorted(G.in_edges(1, data=True)) == [(0, 1, {"data": 0})]
+        assert sorted(G.in_edges(data="data")) == [(0, 1, 0), (1, 0, None)]
+        assert sorted(G.in_edges(1, data="data")) == [(0, 1, 0)]
+
+    def test_degree(self):
+        G = self.K3
+        assert sorted(G.degree()) == [(0, 4), (1, 4), (2, 4)]
+        assert dict(G.degree()) == {0: 4, 1: 4, 2: 4}
+        assert G.degree(0) == 4
+        assert list(G.degree(iter([0]))) == [(0, 4)]  # run through iterator
+
+    def test_in_degree(self):
+        G = self.K3
+        assert sorted(G.in_degree()) == [(0, 2), (1, 2), (2, 2)]
+        assert dict(G.in_degree()) == {0: 2, 1: 2, 2: 2}
+        assert G.in_degree(0) == 2
+        assert list(G.in_degree(iter([0]))) == [(0, 2)]  # run through iterator
+
+    def test_out_degree(self):
+        G = self.K3
+        assert sorted(G.out_degree()) == [(0, 2), (1, 2), (2, 2)]
+        assert dict(G.out_degree()) == {0: 2, 1: 2, 2: 2}
+        assert G.out_degree(0) == 2
+        assert list(G.out_degree(iter([0]))) == [(0, 2)]
+
+    def test_size(self):
+        G = self.K3
+        assert G.size() == 6
+        assert G.number_of_edges() == 6
+
+    def test_to_undirected_reciprocal(self):
+        G = self.Graph()
+        G.add_edge(1, 2)
+        assert G.to_undirected().has_edge(1, 2)
+        assert not G.to_undirected(reciprocal=True).has_edge(1, 2)
+        G.add_edge(2, 1)
+        assert G.to_undirected(reciprocal=True).has_edge(1, 2)
+
+    def test_reverse_copy(self):
+        G = nx.DiGraph([(0, 1), (1, 2)])
+        R = G.reverse()
+        assert sorted(R.edges()) == [(1, 0), (2, 1)]
+        R.remove_edge(1, 0)
+        assert sorted(R.edges()) == [(2, 1)]
+        assert sorted(G.edges()) == [(0, 1), (1, 2)]
+
+    def test_reverse_nocopy(self):
+        G = nx.DiGraph([(0, 1), (1, 2)])
+        R = G.reverse(copy=False)
+        assert sorted(R.edges()) == [(1, 0), (2, 1)]
+        with pytest.raises(nx.NetworkXError):
+            R.remove_edge(1, 0)
+
+    def test_reverse_hashable(self):
+        class Foo:
+            pass
+
+        x = Foo()
+        y = Foo()
+        G = nx.DiGraph()
+        G.add_edge(x, y)
+        assert nodes_equal(G.nodes(), G.reverse().nodes())
+        assert [(y, x)] == list(G.reverse().edges())
+
+    def test_di_cache_reset(self):
+        G = self.K3.copy()
+        old_succ = G.succ
+        assert id(G.succ) == id(old_succ)
+        old_adj = G.adj
+        assert id(G.adj) == id(old_adj)
+
+        G._succ = {}
+        assert id(G.succ) != id(old_succ)
+        assert id(G.adj) != id(old_adj)
+
+        old_pred = G.pred
+        assert id(G.pred) == id(old_pred)
+        G._pred = {}
+        assert id(G.pred) != id(old_pred)
+
+    def test_di_attributes_cached(self):
+        G = self.K3.copy()
+        assert id(G.in_edges) == id(G.in_edges)
+        assert id(G.out_edges) == id(G.out_edges)
+        assert id(G.in_degree) == id(G.in_degree)
+        assert id(G.out_degree) == id(G.out_degree)
+        assert id(G.succ) == id(G.succ)
+        assert id(G.pred) == id(G.pred)
+
+
+class BaseAttrDiGraphTester(BaseDiGraphTester, BaseAttrGraphTester):
+    def test_edges_data(self):
+        G = self.K3
+        all_edges = [
+            (0, 1, {}),
+            (0, 2, {}),
+            (1, 0, {}),
+            (1, 2, {}),
+            (2, 0, {}),
+            (2, 1, {}),
+        ]
+        assert sorted(G.edges(data=True)) == all_edges
+        assert sorted(G.edges(0, data=True)) == all_edges[:2]
+        assert sorted(G.edges([0, 1], data=True)) == all_edges[:4]
+        with pytest.raises(nx.NetworkXError):
+            G.edges(-1, True)
+
+    def test_in_degree_weighted(self):
+        G = self.K3.copy()
+        G.add_edge(0, 1, weight=0.3, other=1.2)
+        assert sorted(G.in_degree(weight="weight")) == [(0, 2), (1, 1.3), (2, 2)]
+        assert dict(G.in_degree(weight="weight")) == {0: 2, 1: 1.3, 2: 2}
+        assert G.in_degree(1, weight="weight") == 1.3
+        assert sorted(G.in_degree(weight="other")) == [(0, 2), (1, 2.2), (2, 2)]
+        assert dict(G.in_degree(weight="other")) == {0: 2, 1: 2.2, 2: 2}
+        assert G.in_degree(1, weight="other") == 2.2
+        assert list(G.in_degree(iter([1]), weight="other")) == [(1, 2.2)]
+
+    def test_out_degree_weighted(self):
+        G = self.K3.copy()
+        G.add_edge(0, 1, weight=0.3, other=1.2)
+        assert sorted(G.out_degree(weight="weight")) == [(0, 1.3), (1, 2), (2, 2)]
+        assert dict(G.out_degree(weight="weight")) == {0: 1.3, 1: 2, 2: 2}
+        assert G.out_degree(0, weight="weight") == 1.3
+        assert sorted(G.out_degree(weight="other")) == [(0, 2.2), (1, 2), (2, 2)]
+        assert dict(G.out_degree(weight="other")) == {0: 2.2, 1: 2, 2: 2}
+        assert G.out_degree(0, weight="other") == 2.2
+        assert list(G.out_degree(iter([0]), weight="other")) == [(0, 2.2)]
+
+
+class TestDiGraph(BaseAttrDiGraphTester, _TestGraph):
+    """Tests specific to dict-of-dict-of-dict digraph data structure"""
+
+    def setup_method(self):
+        self.Graph = nx.DiGraph
+        # build dict-of-dict-of-dict K3
+        ed1, ed2, ed3, ed4, ed5, ed6 = ({}, {}, {}, {}, {}, {})
+        self.k3adj = {0: {1: ed1, 2: ed2}, 1: {0: ed3, 2: ed4}, 2: {0: ed5, 1: ed6}}
+        self.k3edges = [(0, 1), (0, 2), (1, 2)]
+        self.k3nodes = [0, 1, 2]
+        self.K3 = self.Graph()
+        self.K3._succ = self.k3adj  # K3._adj is synced with K3._succ
+        self.K3._pred = {0: {1: ed3, 2: ed5}, 1: {0: ed1, 2: ed6}, 2: {0: ed2, 1: ed4}}
+        self.K3._node = {}
+        self.K3._node[0] = {}
+        self.K3._node[1] = {}
+        self.K3._node[2] = {}
+
+        ed1, ed2 = ({}, {})
+        self.P3 = self.Graph()
+        self.P3._succ = {0: {1: ed1}, 1: {2: ed2}, 2: {}}
+        self.P3._pred = {0: {}, 1: {0: ed1}, 2: {1: ed2}}
+        # P3._adj is synced with P3._succ
+        self.P3._node = {}
+        self.P3._node[0] = {}
+        self.P3._node[1] = {}
+        self.P3._node[2] = {}
+
+    def test_data_input(self):
+        G = self.Graph({1: [2], 2: [1]}, name="test")
+        assert G.name == "test"
+        assert sorted(G.adj.items()) == [(1, {2: {}}), (2, {1: {}})]
+        assert sorted(G.succ.items()) == [(1, {2: {}}), (2, {1: {}})]
+        assert sorted(G.pred.items()) == [(1, {2: {}}), (2, {1: {}})]
+
+    def test_add_edge(self):
+        G = self.Graph()
+        G.add_edge(0, 1)
+        assert G.adj == {0: {1: {}}, 1: {}}
+        assert G.succ == {0: {1: {}}, 1: {}}
+        assert G.pred == {0: {}, 1: {0: {}}}
+        G = self.Graph()
+        G.add_edge(*(0, 1))
+        assert G.adj == {0: {1: {}}, 1: {}}
+        assert G.succ == {0: {1: {}}, 1: {}}
+        assert G.pred == {0: {}, 1: {0: {}}}
+        with pytest.raises(ValueError, match="None cannot be a node"):
+            G.add_edge(None, 3)
+
+    def test_add_edges_from(self):
+        G = self.Graph()
+        G.add_edges_from([(0, 1), (0, 2, {"data": 3})], data=2)
+        assert G.adj == {0: {1: {"data": 2}, 2: {"data": 3}}, 1: {}, 2: {}}
+        assert G.succ == {0: {1: {"data": 2}, 2: {"data": 3}}, 1: {}, 2: {}}
+        assert G.pred == {0: {}, 1: {0: {"data": 2}}, 2: {0: {"data": 3}}}
+
+        with pytest.raises(nx.NetworkXError):
+            G.add_edges_from([(0,)])  # too few in tuple
+        with pytest.raises(nx.NetworkXError):
+            G.add_edges_from([(0, 1, 2, 3)])  # too many in tuple
+        with pytest.raises(TypeError):
+            G.add_edges_from([0])  # not a tuple
+        with pytest.raises(ValueError, match="None cannot be a node"):
+            G.add_edges_from([(None, 3), (3, 2)])
+
+    def test_remove_edge(self):
+        G = self.K3.copy()
+        G.remove_edge(0, 1)
+        assert G.succ == {0: {2: {}}, 1: {0: {}, 2: {}}, 2: {0: {}, 1: {}}}
+        assert G.pred == {0: {1: {}, 2: {}}, 1: {2: {}}, 2: {0: {}, 1: {}}}
+        with pytest.raises(nx.NetworkXError):
+            G.remove_edge(-1, 0)
+
+    def test_remove_edges_from(self):
+        G = self.K3.copy()
+        G.remove_edges_from([(0, 1)])
+        assert G.succ == {0: {2: {}}, 1: {0: {}, 2: {}}, 2: {0: {}, 1: {}}}
+        assert G.pred == {0: {1: {}, 2: {}}, 1: {2: {}}, 2: {0: {}, 1: {}}}
+        G.remove_edges_from([(0, 0)])  # silent fail
+
+    def test_clear(self):
+        G = self.K3
+        G.graph["name"] = "K3"
+        G.clear()
+        assert list(G.nodes) == []
+        assert G.succ == {}
+        assert G.pred == {}
+        assert G.graph == {}
+
+    def test_clear_edges(self):
+        G = self.K3
+        G.graph["name"] = "K3"
+        nodes = list(G.nodes)
+        G.clear_edges()
+        assert list(G.nodes) == nodes
+        expected = {0: {}, 1: {}, 2: {}}
+        assert G.succ == expected
+        assert G.pred == expected
+        assert list(G.edges) == []
+        assert G.graph["name"] == "K3"
+
+
+class TestEdgeSubgraph(_TestGraphEdgeSubgraph):
+    """Unit tests for the :meth:`DiGraph.edge_subgraph` method."""
+
+    def setup_method(self):
+        # Create a doubly-linked path graph on five nodes.
+        G = nx.DiGraph(nx.path_graph(5))
+        # Add some node, edge, and graph attributes.
+        for i in range(5):
+            G.nodes[i]["name"] = f"node{i}"
+        G.edges[0, 1]["name"] = "edge01"
+        G.edges[3, 4]["name"] = "edge34"
+        G.graph["name"] = "graph"
+        # Get the subgraph induced by the first and last edges.
+        self.G = G
+        self.H = G.edge_subgraph([(0, 1), (3, 4)])
+
+    def test_pred_succ(self):
+        """Test that nodes are added to predecessors and successors.
+
+        For more information, see GitHub issue #2370.
+
+        """
+        G = nx.DiGraph()
+        G.add_edge(0, 1)
+        H = G.edge_subgraph([(0, 1)])
+        assert list(H.predecessors(0)) == []
+        assert list(H.successors(0)) == [1]
+        assert list(H.predecessors(1)) == [0]
+        assert list(H.successors(1)) == []

venv/lib/python3.10/site-packages/networkx/classes/tests/test_digraph_historical.py

@@ -0,0 +1,110 @@
+"""Original NetworkX graph tests"""
+import pytest
+
+import networkx
+import networkx as nx
+
+from .historical_tests import HistoricalTests
+
+
+class TestDiGraphHistorical(HistoricalTests):
+    @classmethod
+    def setup_class(cls):
+        HistoricalTests.setup_class()
+        cls.G = nx.DiGraph
+
+    def test_in_degree(self):
+        G = self.G()
+        G.add_nodes_from("GJK")
+        G.add_edges_from([("A", "B"), ("A", "C"), ("B", "D"), ("B", "C"), ("C", "D")])
+
+        assert sorted(d for n, d in G.in_degree()) == [0, 0, 0, 0, 1, 2, 2]
+        assert dict(G.in_degree()) == {
+            "A": 0,
+            "C": 2,
+            "B": 1,
+            "D": 2,
+            "G": 0,
+            "K": 0,
+            "J": 0,
+        }
+
+    def test_out_degree(self):
+        G = self.G()
+        G.add_nodes_from("GJK")
+        G.add_edges_from([("A", "B"), ("A", "C"), ("B", "D"), ("B", "C"), ("C", "D")])
+        assert sorted(v for k, v in G.in_degree()) == [0, 0, 0, 0, 1, 2, 2]
+        assert dict(G.out_degree()) == {
+            "A": 2,
+            "C": 1,
+            "B": 2,
+            "D": 0,
+            "G": 0,
+            "K": 0,
+            "J": 0,
+        }
+
+    def test_degree_digraph(self):
+        H = nx.DiGraph()
+        H.add_edges_from([(1, 24), (1, 2)])
+        assert sorted(d for n, d in H.in_degree([1, 24])) == [0, 1]
+        assert sorted(d for n, d in H.out_degree([1, 24])) == [0, 2]
+        assert sorted(d for n, d in H.degree([1, 24])) == [1, 2]
+
+    def test_neighbors(self):
+        G = self.G()
+        G.add_nodes_from("GJK")
+        G.add_edges_from([("A", "B"), ("A", "C"), ("B", "D"), ("B", "C"), ("C", "D")])
+
+        assert sorted(G.neighbors("C")) == ["D"]
+        assert sorted(G["C"]) == ["D"]
+        assert sorted(G.neighbors("A")) == ["B", "C"]
+        pytest.raises(nx.NetworkXError, G.neighbors, "j")
+        pytest.raises(nx.NetworkXError, G.neighbors, "j")
+
+    def test_successors(self):
+        G = self.G()
+        G.add_nodes_from("GJK")
+        G.add_edges_from([("A", "B"), ("A", "C"), ("B", "D"), ("B", "C"), ("C", "D")])
+        assert sorted(G.successors("A")) == ["B", "C"]
+        assert sorted(G.successors("A")) == ["B", "C"]
+        assert sorted(G.successors("G")) == []
+        assert sorted(G.successors("D")) == []
+        assert sorted(G.successors("G")) == []
+        pytest.raises(nx.NetworkXError, G.successors, "j")
+        pytest.raises(nx.NetworkXError, G.successors, "j")
+
+    def test_predecessors(self):
+        G = self.G()
+        G.add_nodes_from("GJK")
+        G.add_edges_from([("A", "B"), ("A", "C"), ("B", "D"), ("B", "C"), ("C", "D")])
+        assert sorted(G.predecessors("C")) == ["A", "B"]
+        assert sorted(G.predecessors("C")) == ["A", "B"]
+        assert sorted(G.predecessors("G")) == []
+        assert sorted(G.predecessors("A")) == []
+        assert sorted(G.predecessors("G")) == []
+        assert sorted(G.predecessors("A")) == []
+        assert sorted(G.successors("D")) == []
+
+        pytest.raises(nx.NetworkXError, G.predecessors, "j")
+        pytest.raises(nx.NetworkXError, G.predecessors, "j")
+
+    def test_reverse(self):
+        G = nx.complete_graph(10)
+        H = G.to_directed()
+        HR = H.reverse()
+        assert nx.is_isomorphic(H, HR)
+        assert sorted(H.edges()) == sorted(HR.edges())
+
+    def test_reverse2(self):
+        H = nx.DiGraph()
+        foo = [H.add_edge(u, u + 1) for u in range(5)]
+        HR = H.reverse()
+        for u in range(5):
+            assert HR.has_edge(u + 1, u)
+
+    def test_reverse3(self):
+        H = nx.DiGraph()
+        H.add_nodes_from([1, 2, 3, 4])
+        HR = H.reverse()
+        assert sorted(HR.nodes()) == [1, 2, 3, 4]

venv/lib/python3.10/site-packages/networkx/classes/tests/test_graph.py

@@ -0,0 +1,920 @@
+import gc
+import pickle
+import platform
+import weakref
+
+import pytest
+
+import networkx as nx
+from networkx.utils import edges_equal, graphs_equal, nodes_equal
+
+
+class BaseGraphTester:
+    """Tests for data-structure independent graph class features."""
+
+    def test_contains(self):
+        G = self.K3
+        assert 1 in G
+        assert 4 not in G
+        assert "b" not in G
+        assert [] not in G  # no exception for nonhashable
+        assert {1: 1} not in G  # no exception for nonhashable
+
+    def test_order(self):
+        G = self.K3
+        assert len(G) == 3
+        assert G.order() == 3
+        assert G.number_of_nodes() == 3
+
+    def test_nodes(self):
+        G = self.K3
+        assert isinstance(G._node, G.node_dict_factory)
+        assert isinstance(G._adj, G.adjlist_outer_dict_factory)
+        assert all(
+            isinstance(adj, G.adjlist_inner_dict_factory) for adj in G._adj.values()
+        )
+        assert sorted(G.nodes()) == self.k3nodes
+        assert sorted(G.nodes(data=True)) == [(0, {}), (1, {}), (2, {})]
+
+    def test_none_node(self):
+        G = self.Graph()
+        with pytest.raises(ValueError):
+            G.add_node(None)
+        with pytest.raises(ValueError):
+            G.add_nodes_from([None])
+        with pytest.raises(ValueError):
+            G.add_edge(0, None)
+        with pytest.raises(ValueError):
+            G.add_edges_from([(0, None)])
+
+    def test_has_node(self):
+        G = self.K3
+        assert G.has_node(1)
+        assert not G.has_node(4)
+        assert not G.has_node([])  # no exception for nonhashable
+        assert not G.has_node({1: 1})  # no exception for nonhashable
+
+    def test_has_edge(self):
+        G = self.K3
+        assert G.has_edge(0, 1)
+        assert not G.has_edge(0, -1)
+
+    def test_neighbors(self):
+        G = self.K3
+        assert sorted(G.neighbors(0)) == [1, 2]
+        with pytest.raises(nx.NetworkXError):
+            G.neighbors(-1)
+
+    @pytest.mark.skipif(
+        platform.python_implementation() == "PyPy", reason="PyPy gc is different"
+    )
+    def test_memory_leak(self):
+        G = self.Graph()
+
+        def count_objects_of_type(_type):
+            # Iterating over all objects tracked by gc can include weak references
+            # whose weakly-referenced objects may no longer exist. Calling `isinstance`
+            # on such a weak reference will raise ReferenceError. There are at least
+            # three workarounds for this: one is to compare type names instead of using
+            # `isinstance` such as `type(obj).__name__ == typename`, another is to use
+            # `type(obj) == _type`, and the last is to ignore ProxyTypes as we do below.
+            # NOTE: even if this safeguard is deemed unnecessary to pass NetworkX tests,
+            # we should still keep it for maximum safety for other NetworkX backends.
+            return sum(
+                1
+                for obj in gc.get_objects()
+                if not isinstance(obj, weakref.ProxyTypes) and isinstance(obj, _type)
+            )
+
+        gc.collect()
+        before = count_objects_of_type(self.Graph)
+        G.copy()
+        gc.collect()
+        after = count_objects_of_type(self.Graph)
+        assert before == after
+
+        # test a subgraph of the base class
+        class MyGraph(self.Graph):
+            pass
+
+        gc.collect()
+        G = MyGraph()
+        before = count_objects_of_type(MyGraph)
+        G.copy()
+        gc.collect()
+        after = count_objects_of_type(MyGraph)
+        assert before == after
+
+    def test_edges(self):
+        G = self.K3
+        assert isinstance(G._adj, G.adjlist_outer_dict_factory)
+        assert edges_equal(G.edges(), [(0, 1), (0, 2), (1, 2)])
+        assert edges_equal(G.edges(0), [(0, 1), (0, 2)])
+        assert edges_equal(G.edges([0, 1]), [(0, 1), (0, 2), (1, 2)])
+        with pytest.raises(nx.NetworkXError):
+            G.edges(-1)
+
+    def test_degree(self):
+        G = self.K3
+        assert sorted(G.degree()) == [(0, 2), (1, 2), (2, 2)]
+        assert dict(G.degree()) == {0: 2, 1: 2, 2: 2}
+        assert G.degree(0) == 2
+        with pytest.raises(nx.NetworkXError):
+            G.degree(-1)  # node not in graph
+
+    def test_size(self):
+        G = self.K3
+        assert G.size() == 3
+        assert G.number_of_edges() == 3
+
+    def test_nbunch_iter(self):
+        G = self.K3
+        assert nodes_equal(G.nbunch_iter(), self.k3nodes)  # all nodes
+        assert nodes_equal(G.nbunch_iter(0), [0])  # single node
+        assert nodes_equal(G.nbunch_iter([0, 1]), [0, 1])  # sequence
+        # sequence with none in graph
+        assert nodes_equal(G.nbunch_iter([-1]), [])
+        # string sequence with none in graph
+        assert nodes_equal(G.nbunch_iter("foo"), [])
+        # node not in graph doesn't get caught upon creation of iterator
+        bunch = G.nbunch_iter(-1)
+        # but gets caught when iterator used
+        with pytest.raises(nx.NetworkXError, match="is not a node or a sequence"):
+            list(bunch)
+        # unhashable doesn't get caught upon creation of iterator
+        bunch = G.nbunch_iter([0, 1, 2, {}])
+        # but gets caught when iterator hits the unhashable
+        with pytest.raises(
+            nx.NetworkXError, match="in sequence nbunch is not a valid node"
+        ):
+            list(bunch)
+
+    def test_nbunch_iter_node_format_raise(self):
+        # Tests that a node that would have failed string formatting
+        # doesn't cause an error when attempting to raise a
+        # :exc:`nx.NetworkXError`.
+
+        # For more information, see pull request #1813.
+        G = self.Graph()
+        nbunch = [("x", set())]
+        with pytest.raises(nx.NetworkXError):
+            list(G.nbunch_iter(nbunch))
+
+    def test_selfloop_degree(self):
+        G = self.Graph()
+        G.add_edge(1, 1)
+        assert sorted(G.degree()) == [(1, 2)]
+        assert dict(G.degree()) == {1: 2}
+        assert G.degree(1) == 2
+        assert sorted(G.degree([1])) == [(1, 2)]
+        assert G.degree(1, weight="weight") == 2
+
+    def test_selfloops(self):
+        G = self.K3.copy()
+        G.add_edge(0, 0)
+        assert nodes_equal(nx.nodes_with_selfloops(G), [0])
+        assert edges_equal(nx.selfloop_edges(G), [(0, 0)])
+        assert nx.number_of_selfloops(G) == 1
+        G.remove_edge(0, 0)
+        G.add_edge(0, 0)
+        G.remove_edges_from([(0, 0)])
+        G.add_edge(1, 1)
+        G.remove_node(1)
+        G.add_edge(0, 0)
+        G.add_edge(1, 1)
+        G.remove_nodes_from([0, 1])
+
+    def test_cache_reset(self):
+        G = self.K3.copy()
+        old_adj = G.adj
+        assert id(G.adj) == id(old_adj)
+        G._adj = {}
+        assert id(G.adj) != id(old_adj)
+
+        old_nodes = G.nodes
+        assert id(G.nodes) == id(old_nodes)
+        G._node = {}
+        assert id(G.nodes) != id(old_nodes)
+
+    def test_attributes_cached(self):
+        G = self.K3.copy()
+        assert id(G.nodes) == id(G.nodes)
+        assert id(G.edges) == id(G.edges)
+        assert id(G.degree) == id(G.degree)
+        assert id(G.adj) == id(G.adj)
+
+
+class BaseAttrGraphTester(BaseGraphTester):
+    """Tests of graph class attribute features."""
+
+    def test_weighted_degree(self):
+        G = self.Graph()
+        G.add_edge(1, 2, weight=2, other=3)
+        G.add_edge(2, 3, weight=3, other=4)
+        assert sorted(d for n, d in G.degree(weight="weight")) == [2, 3, 5]
+        assert dict(G.degree(weight="weight")) == {1: 2, 2: 5, 3: 3}
+        assert G.degree(1, weight="weight") == 2
+        assert nodes_equal((G.degree([1], weight="weight")), [(1, 2)])
+
+        assert nodes_equal((d for n, d in G.degree(weight="other")), [3, 7, 4])
+        assert dict(G.degree(weight="other")) == {1: 3, 2: 7, 3: 4}
+        assert G.degree(1, weight="other") == 3
+        assert edges_equal((G.degree([1], weight="other")), [(1, 3)])
+
+    def add_attributes(self, G):
+        G.graph["foo"] = []
+        G.nodes[0]["foo"] = []
+        G.remove_edge(1, 2)
+        ll = []
+        G.add_edge(1, 2, foo=ll)
+        G.add_edge(2, 1, foo=ll)
+
+    def test_name(self):
+        G = self.Graph(name="")
+        assert G.name == ""
+        G = self.Graph(name="test")
+        assert G.name == "test"
+
+    def test_str_unnamed(self):
+        G = self.Graph()
+        G.add_edges_from([(1, 2), (2, 3)])
+        assert str(G) == f"{type(G).__name__} with 3 nodes and 2 edges"
+
+    def test_str_named(self):
+        G = self.Graph(name="foo")
+        G.add_edges_from([(1, 2), (2, 3)])
+        assert str(G) == f"{type(G).__name__} named 'foo' with 3 nodes and 2 edges"
+
+    def test_graph_chain(self):
+        G = self.Graph([(0, 1), (1, 2)])
+        DG = G.to_directed(as_view=True)
+        SDG = DG.subgraph([0, 1])
+        RSDG = SDG.reverse(copy=False)
+        assert G is DG._graph
+        assert DG is SDG._graph
+        assert SDG is RSDG._graph
+
+    def test_copy(self):
+        G = self.Graph()
+        G.add_node(0)
+        G.add_edge(1, 2)
+        self.add_attributes(G)
+        # copy edge datadict but any container attr are same
+        H = G.copy()
+        self.graphs_equal(H, G)
+        self.different_attrdict(H, G)
+        self.shallow_copy_attrdict(H, G)
+
+    def test_class_copy(self):
+        G = self.Graph()
+        G.add_node(0)
+        G.add_edge(1, 2)
+        self.add_attributes(G)
+        # copy edge datadict but any container attr are same
+        H = G.__class__(G)
+        self.graphs_equal(H, G)
+        self.different_attrdict(H, G)
+        self.shallow_copy_attrdict(H, G)
+
+    def test_fresh_copy(self):
+        G = self.Graph()
+        G.add_node(0)
+        G.add_edge(1, 2)
+        self.add_attributes(G)
+        # copy graph structure but use fresh datadict
+        H = G.__class__()
+        H.add_nodes_from(G)
+        H.add_edges_from(G.edges())
+        assert len(G.nodes[0]) == 1
+        ddict = G.adj[1][2][0] if G.is_multigraph() else G.adj[1][2]
+        assert len(ddict) == 1
+        assert len(H.nodes[0]) == 0
+        ddict = H.adj[1][2][0] if H.is_multigraph() else H.adj[1][2]
+        assert len(ddict) == 0
+
+    def is_deepcopy(self, H, G):
+        self.graphs_equal(H, G)
+        self.different_attrdict(H, G)
+        self.deep_copy_attrdict(H, G)
+
+    def deep_copy_attrdict(self, H, G):
+        self.deepcopy_graph_attr(H, G)
+        self.deepcopy_node_attr(H, G)
+        self.deepcopy_edge_attr(H, G)
+
+    def deepcopy_graph_attr(self, H, G):
+        assert G.graph["foo"] == H.graph["foo"]
+        G.graph["foo"].append(1)
+        assert G.graph["foo"] != H.graph["foo"]
+
+    def deepcopy_node_attr(self, H, G):
+        assert G.nodes[0]["foo"] == H.nodes[0]["foo"]
+        G.nodes[0]["foo"].append(1)
+        assert G.nodes[0]["foo"] != H.nodes[0]["foo"]
+
+    def deepcopy_edge_attr(self, H, G):
+        assert G[1][2]["foo"] == H[1][2]["foo"]
+        G[1][2]["foo"].append(1)
+        assert G[1][2]["foo"] != H[1][2]["foo"]
+
+    def is_shallow_copy(self, H, G):
+        self.graphs_equal(H, G)
+        self.shallow_copy_attrdict(H, G)
+
+    def shallow_copy_attrdict(self, H, G):
+        self.shallow_copy_graph_attr(H, G)
+        self.shallow_copy_node_attr(H, G)
+        self.shallow_copy_edge_attr(H, G)
+
+    def shallow_copy_graph_attr(self, H, G):
+        assert G.graph["foo"] == H.graph["foo"]
+        G.graph["foo"].append(1)
+        assert G.graph["foo"] == H.graph["foo"]
+
+    def shallow_copy_node_attr(self, H, G):
+        assert G.nodes[0]["foo"] == H.nodes[0]["foo"]
+        G.nodes[0]["foo"].append(1)
+        assert G.nodes[0]["foo"] == H.nodes[0]["foo"]
+
+    def shallow_copy_edge_attr(self, H, G):
+        assert G[1][2]["foo"] == H[1][2]["foo"]
+        G[1][2]["foo"].append(1)
+        assert G[1][2]["foo"] == H[1][2]["foo"]
+
+    def same_attrdict(self, H, G):
+        old_foo = H[1][2]["foo"]
+        H.adj[1][2]["foo"] = "baz"
+        assert G.edges == H.edges
+        H.adj[1][2]["foo"] = old_foo
+        assert G.edges == H.edges
+
+        old_foo = H.nodes[0]["foo"]
+        H.nodes[0]["foo"] = "baz"
+        assert G.nodes == H.nodes
+        H.nodes[0]["foo"] = old_foo
+        assert G.nodes == H.nodes
+
+    def different_attrdict(self, H, G):
+        old_foo = H[1][2]["foo"]
+        H.adj[1][2]["foo"] = "baz"
+        assert G._adj != H._adj
+        H.adj[1][2]["foo"] = old_foo
+        assert G._adj == H._adj
+
+        old_foo = H.nodes[0]["foo"]
+        H.nodes[0]["foo"] = "baz"
+        assert G._node != H._node
+        H.nodes[0]["foo"] = old_foo
+        assert G._node == H._node
+
+    def graphs_equal(self, H, G):
+        assert G._adj == H._adj
+        assert G._node == H._node
+        assert G.graph == H.graph
+        assert G.name == H.name
+        if not G.is_directed() and not H.is_directed():
+            assert H._adj[1][2] is H._adj[2][1]
+            assert G._adj[1][2] is G._adj[2][1]
+        else:  # at least one is directed
+            if not G.is_directed():
+                G._pred = G._adj
+                G._succ = G._adj
+            if not H.is_directed():
+                H._pred = H._adj
+                H._succ = H._adj
+            assert G._pred == H._pred
+            assert G._succ == H._succ
+            assert H._succ[1][2] is H._pred[2][1]
+            assert G._succ[1][2] is G._pred[2][1]
+
+    def test_graph_attr(self):
+        G = self.K3.copy()
+        G.graph["foo"] = "bar"
+        assert isinstance(G.graph, G.graph_attr_dict_factory)
+        assert G.graph["foo"] == "bar"
+        del G.graph["foo"]
+        assert G.graph == {}
+        H = self.Graph(foo="bar")
+        assert H.graph["foo"] == "bar"
+
+    def test_node_attr(self):
+        G = self.K3.copy()
+        G.add_node(1, foo="bar")
+        assert all(
+            isinstance(d, G.node_attr_dict_factory) for u, d in G.nodes(data=True)
+        )
+        assert nodes_equal(G.nodes(), [0, 1, 2])
+        assert nodes_equal(G.nodes(data=True), [(0, {}), (1, {"foo": "bar"}), (2, {})])
+        G.nodes[1]["foo"] = "baz"
+        assert nodes_equal(G.nodes(data=True), [(0, {}), (1, {"foo": "baz"}), (2, {})])
+        assert nodes_equal(G.nodes(data="foo"), [(0, None), (1, "baz"), (2, None)])
+        assert nodes_equal(
+            G.nodes(data="foo", default="bar"), [(0, "bar"), (1, "baz"), (2, "bar")]
+        )
+
+    def test_node_attr2(self):
+        G = self.K3.copy()
+        a = {"foo": "bar"}
+        G.add_node(3, **a)
+        assert nodes_equal(G.nodes(), [0, 1, 2, 3])
+        assert nodes_equal(
+            G.nodes(data=True), [(0, {}), (1, {}), (2, {}), (3, {"foo": "bar"})]
+        )
+
+    def test_edge_lookup(self):
+        G = self.Graph()
+        G.add_edge(1, 2, foo="bar")
+        assert edges_equal(G.edges[1, 2], {"foo": "bar"})
+
+    def test_edge_attr(self):
+        G = self.Graph()
+        G.add_edge(1, 2, foo="bar")
+        assert all(
+            isinstance(d, G.edge_attr_dict_factory) for u, v, d in G.edges(data=True)
+        )
+        assert edges_equal(G.edges(data=True), [(1, 2, {"foo": "bar"})])
+        assert edges_equal(G.edges(data="foo"), [(1, 2, "bar")])
+
+    def test_edge_attr2(self):
+        G = self.Graph()
+        G.add_edges_from([(1, 2), (3, 4)], foo="foo")
+        assert edges_equal(
+            G.edges(data=True), [(1, 2, {"foo": "foo"}), (3, 4, {"foo": "foo"})]
+        )
+        assert edges_equal(G.edges(data="foo"), [(1, 2, "foo"), (3, 4, "foo")])
+
+    def test_edge_attr3(self):
+        G = self.Graph()
+        G.add_edges_from([(1, 2, {"weight": 32}), (3, 4, {"weight": 64})], foo="foo")
+        assert edges_equal(
+            G.edges(data=True),
+            [
+                (1, 2, {"foo": "foo", "weight": 32}),
+                (3, 4, {"foo": "foo", "weight": 64}),
+            ],
+        )
+
+        G.remove_edges_from([(1, 2), (3, 4)])
+        G.add_edge(1, 2, data=7, spam="bar", bar="foo")
+        assert edges_equal(
+            G.edges(data=True), [(1, 2, {"data": 7, "spam": "bar", "bar": "foo"})]
+        )
+
+    def test_edge_attr4(self):
+        G = self.Graph()
+        G.add_edge(1, 2, data=7, spam="bar", bar="foo")
+        assert edges_equal(
+            G.edges(data=True), [(1, 2, {"data": 7, "spam": "bar", "bar": "foo"})]
+        )
+        G[1][2]["data"] = 10  # OK to set data like this
+        assert edges_equal(
+            G.edges(data=True), [(1, 2, {"data": 10, "spam": "bar", "bar": "foo"})]
+        )
+
+        G.adj[1][2]["data"] = 20
+        assert edges_equal(
+            G.edges(data=True), [(1, 2, {"data": 20, "spam": "bar", "bar": "foo"})]
+        )
+        G.edges[1, 2]["data"] = 21  # another spelling, "edge"
+        assert edges_equal(
+            G.edges(data=True), [(1, 2, {"data": 21, "spam": "bar", "bar": "foo"})]
+        )
+        G.adj[1][2]["listdata"] = [20, 200]
+        G.adj[1][2]["weight"] = 20
+        dd = {
+            "data": 21,
+            "spam": "bar",
+            "bar": "foo",
+            "listdata": [20, 200],
+            "weight": 20,
+        }
+        assert edges_equal(G.edges(data=True), [(1, 2, dd)])
+
+    def test_to_undirected(self):
+        G = self.K3
+        self.add_attributes(G)
+        H = nx.Graph(G)
+        self.is_shallow_copy(H, G)
+        self.different_attrdict(H, G)
+        H = G.to_undirected()
+        self.is_deepcopy(H, G)
+
+    def test_to_directed_as_view(self):
+        H = nx.path_graph(2, create_using=self.Graph)
+        H2 = H.to_directed(as_view=True)
+        assert H is H2._graph
+        assert H2.has_edge(0, 1)
+        assert H2.has_edge(1, 0) or H.is_directed()
+        pytest.raises(nx.NetworkXError, H2.add_node, -1)
+        pytest.raises(nx.NetworkXError, H2.add_edge, 1, 2)
+        H.add_edge(1, 2)
+        assert H2.has_edge(1, 2)
+        assert H2.has_edge(2, 1) or H.is_directed()
+
+    def test_to_undirected_as_view(self):
+        H = nx.path_graph(2, create_using=self.Graph)
+        H2 = H.to_undirected(as_view=True)
+        assert H is H2._graph
+        assert H2.has_edge(0, 1)
+        assert H2.has_edge(1, 0)
+        pytest.raises(nx.NetworkXError, H2.add_node, -1)
+        pytest.raises(nx.NetworkXError, H2.add_edge, 1, 2)
+        H.add_edge(1, 2)
+        assert H2.has_edge(1, 2)
+        assert H2.has_edge(2, 1)
+
+    def test_directed_class(self):
+        G = self.Graph()
+
+        class newGraph(G.to_undirected_class()):
+            def to_directed_class(self):
+                return newDiGraph
+
+            def to_undirected_class(self):
+                return newGraph
+
+        class newDiGraph(G.to_directed_class()):
+            def to_directed_class(self):
+                return newDiGraph
+
+            def to_undirected_class(self):
+                return newGraph
+
+        G = newDiGraph() if G.is_directed() else newGraph()
+        H = G.to_directed()
+        assert isinstance(H, newDiGraph)
+        H = G.to_undirected()
+        assert isinstance(H, newGraph)
+
+    def test_to_directed(self):
+        G = self.K3
+        self.add_attributes(G)
+        H = nx.DiGraph(G)
+        self.is_shallow_copy(H, G)
+        self.different_attrdict(H, G)
+        H = G.to_directed()
+        self.is_deepcopy(H, G)
+
+    def test_subgraph(self):
+        G = self.K3
+        self.add_attributes(G)
+        H = G.subgraph([0, 1, 2, 5])
+        self.graphs_equal(H, G)
+        self.same_attrdict(H, G)
+        self.shallow_copy_attrdict(H, G)
+
+        H = G.subgraph(0)
+        assert H.adj == {0: {}}
+        H = G.subgraph([])
+        assert H.adj == {}
+        assert G.adj != {}
+
+    def test_selfloops_attr(self):
+        G = self.K3.copy()
+        G.add_edge(0, 0)
+        G.add_edge(1, 1, weight=2)
+        assert edges_equal(
+            nx.selfloop_edges(G, data=True), [(0, 0, {}), (1, 1, {"weight": 2})]
+        )
+        assert edges_equal(
+            nx.selfloop_edges(G, data="weight"), [(0, 0, None), (1, 1, 2)]
+        )
+
+
+class TestGraph(BaseAttrGraphTester):
+    """Tests specific to dict-of-dict-of-dict graph data structure"""
+
+    def setup_method(self):
+        self.Graph = nx.Graph
+        # build dict-of-dict-of-dict K3
+        ed1, ed2, ed3 = ({}, {}, {})
+        self.k3adj = {0: {1: ed1, 2: ed2}, 1: {0: ed1, 2: ed3}, 2: {0: ed2, 1: ed3}}
+        self.k3edges = [(0, 1), (0, 2), (1, 2)]
+        self.k3nodes = [0, 1, 2]
+        self.K3 = self.Graph()
+        self.K3._adj = self.k3adj
+        self.K3._node = {}
+        self.K3._node[0] = {}
+        self.K3._node[1] = {}
+        self.K3._node[2] = {}
+
+    def test_pickle(self):
+        G = self.K3
+        pg = pickle.loads(pickle.dumps(G, -1))
+        self.graphs_equal(pg, G)
+        pg = pickle.loads(pickle.dumps(G))
+        self.graphs_equal(pg, G)
+
+    def test_data_input(self):
+        G = self.Graph({1: [2], 2: [1]}, name="test")
+        assert G.name == "test"
+        assert sorted(G.adj.items()) == [(1, {2: {}}), (2, {1: {}})]
+
+    def test_adjacency(self):
+        G = self.K3
+        assert dict(G.adjacency()) == {
+            0: {1: {}, 2: {}},
+            1: {0: {}, 2: {}},
+            2: {0: {}, 1: {}},
+        }
+
+    def test_getitem(self):
+        G = self.K3
+        assert G.adj[0] == {1: {}, 2: {}}
+        assert G[0] == {1: {}, 2: {}}
+        with pytest.raises(KeyError):
+            G.__getitem__("j")
+        with pytest.raises(TypeError):
+            G.__getitem__(["A"])
+
+    def test_add_node(self):
+        G = self.Graph()
+        G.add_node(0)
+        assert G.adj == {0: {}}
+        # test add attributes
+        G.add_node(1, c="red")
+        G.add_node(2, c="blue")
+        G.add_node(3, c="red")
+        assert G.nodes[1]["c"] == "red"
+        assert G.nodes[2]["c"] == "blue"
+        assert G.nodes[3]["c"] == "red"
+        # test updating attributes
+        G.add_node(1, c="blue")
+        G.add_node(2, c="red")
+        G.add_node(3, c="blue")
+        assert G.nodes[1]["c"] == "blue"
+        assert G.nodes[2]["c"] == "red"
+        assert G.nodes[3]["c"] == "blue"
+
+    def test_add_nodes_from(self):
+        G = self.Graph()
+        G.add_nodes_from([0, 1, 2])
+        assert G.adj == {0: {}, 1: {}, 2: {}}
+        # test add attributes
+        G.add_nodes_from([0, 1, 2], c="red")
+        assert G.nodes[0]["c"] == "red"
+        assert G.nodes[2]["c"] == "red"
+        # test that attribute dicts are not the same
+        assert G.nodes[0] is not G.nodes[1]
+        # test updating attributes
+        G.add_nodes_from([0, 1, 2], c="blue")
+        assert G.nodes[0]["c"] == "blue"
+        assert G.nodes[2]["c"] == "blue"
+        assert G.nodes[0] is not G.nodes[1]
+        # test tuple input
+        H = self.Graph()
+        H.add_nodes_from(G.nodes(data=True))
+        assert H.nodes[0]["c"] == "blue"
+        assert H.nodes[2]["c"] == "blue"
+        assert H.nodes[0] is not H.nodes[1]
+        # specific overrides general
+        H.add_nodes_from([0, (1, {"c": "green"}), (3, {"c": "cyan"})], c="red")
+        assert H.nodes[0]["c"] == "red"
+        assert H.nodes[1]["c"] == "green"
+        assert H.nodes[2]["c"] == "blue"
+        assert H.nodes[3]["c"] == "cyan"
+
+    def test_remove_node(self):
+        G = self.K3.copy()
+        G.remove_node(0)
+        assert G.adj == {1: {2: {}}, 2: {1: {}}}
+        with pytest.raises(nx.NetworkXError):
+            G.remove_node(-1)
+
+        # generator here to implement list,set,string...
+
+    def test_remove_nodes_from(self):
+        G = self.K3.copy()
+        G.remove_nodes_from([0, 1])
+        assert G.adj == {2: {}}
+        G.remove_nodes_from([-1])  # silent fail
+
+    def test_add_edge(self):
+        G = self.Graph()
+        G.add_edge(0, 1)
+        assert G.adj == {0: {1: {}}, 1: {0: {}}}
+        G = self.Graph()
+        G.add_edge(*(0, 1))
+        assert G.adj == {0: {1: {}}, 1: {0: {}}}
+        G = self.Graph()
+        with pytest.raises(ValueError):
+            G.add_edge(None, "anything")
+
+    def test_add_edges_from(self):
+        G = self.Graph()
+        G.add_edges_from([(0, 1), (0, 2, {"weight": 3})])
+        assert G.adj == {
+            0: {1: {}, 2: {"weight": 3}},
+            1: {0: {}},
+            2: {0: {"weight": 3}},
+        }
+        G = self.Graph()
+        G.add_edges_from([(0, 1), (0, 2, {"weight": 3}), (1, 2, {"data": 4})], data=2)
+        assert G.adj == {
+            0: {1: {"data": 2}, 2: {"weight": 3, "data": 2}},
+            1: {0: {"data": 2}, 2: {"data": 4}},
+            2: {0: {"weight": 3, "data": 2}, 1: {"data": 4}},
+        }
+
+        with pytest.raises(nx.NetworkXError):
+            G.add_edges_from([(0,)])  # too few in tuple
+        with pytest.raises(nx.NetworkXError):
+            G.add_edges_from([(0, 1, 2, 3)])  # too many in tuple
+        with pytest.raises(TypeError):
+            G.add_edges_from([0])  # not a tuple
+        with pytest.raises(ValueError):
+            G.add_edges_from([(None, 3), (3, 2)])  # None cannot be a node
+
+    def test_remove_edge(self):
+        G = self.K3.copy()
+        G.remove_edge(0, 1)
+        assert G.adj == {0: {2: {}}, 1: {2: {}}, 2: {0: {}, 1: {}}}
+        with pytest.raises(nx.NetworkXError):
+            G.remove_edge(-1, 0)
+
+    def test_remove_edges_from(self):
+        G = self.K3.copy()
+        G.remove_edges_from([(0, 1)])
+        assert G.adj == {0: {2: {}}, 1: {2: {}}, 2: {0: {}, 1: {}}}
+        G.remove_edges_from([(0, 0)])  # silent fail
+
+    def test_clear(self):
+        G = self.K3.copy()
+        G.graph["name"] = "K3"
+        G.clear()
+        assert list(G.nodes) == []
+        assert G.adj == {}
+        assert G.graph == {}
+
+    def test_clear_edges(self):
+        G = self.K3.copy()
+        G.graph["name"] = "K3"
+        nodes = list(G.nodes)
+        G.clear_edges()
+        assert list(G.nodes) == nodes
+        assert G.adj == {0: {}, 1: {}, 2: {}}
+        assert list(G.edges) == []
+        assert G.graph["name"] == "K3"
+
+    def test_edges_data(self):
+        G = self.K3
+        all_edges = [(0, 1, {}), (0, 2, {}), (1, 2, {})]
+        assert edges_equal(G.edges(data=True), all_edges)
+        assert edges_equal(G.edges(0, data=True), [(0, 1, {}), (0, 2, {})])
+        assert edges_equal(G.edges([0, 1], data=True), all_edges)
+        with pytest.raises(nx.NetworkXError):
+            G.edges(-1, True)
+
+    def test_get_edge_data(self):
+        G = self.K3.copy()
+        assert G.get_edge_data(0, 1) == {}
+        assert G[0][1] == {}
+        assert G.get_edge_data(10, 20) is None
+        assert G.get_edge_data(-1, 0) is None
+        assert G.get_edge_data(-1, 0, default=1) == 1
+
+    def test_update(self):
+        # specify both edges and nodes
+        G = self.K3.copy()
+        G.update(nodes=[3, (4, {"size": 2})], edges=[(4, 5), (6, 7, {"weight": 2})])
+        nlist = [
+            (0, {}),
+            (1, {}),
+            (2, {}),
+            (3, {}),
+            (4, {"size": 2}),
+            (5, {}),
+            (6, {}),
+            (7, {}),
+        ]
+        assert sorted(G.nodes.data()) == nlist
+        if G.is_directed():
+            elist = [
+                (0, 1, {}),
+                (0, 2, {}),
+                (1, 0, {}),
+                (1, 2, {}),
+                (2, 0, {}),
+                (2, 1, {}),
+                (4, 5, {}),
+                (6, 7, {"weight": 2}),
+            ]
+        else:
+            elist = [
+                (0, 1, {}),
+                (0, 2, {}),
+                (1, 2, {}),
+                (4, 5, {}),
+                (6, 7, {"weight": 2}),
+            ]
+        assert sorted(G.edges.data()) == elist
+        assert G.graph == {}
+
+        # no keywords -- order is edges, nodes
+        G = self.K3.copy()
+        G.update([(4, 5), (6, 7, {"weight": 2})], [3, (4, {"size": 2})])
+        assert sorted(G.nodes.data()) == nlist
+        assert sorted(G.edges.data()) == elist
+        assert G.graph == {}
+
+        # update using only a graph
+        G = self.Graph()
+        G.graph["foo"] = "bar"
+        G.add_node(2, data=4)
+        G.add_edge(0, 1, weight=0.5)
+        GG = G.copy()
+        H = self.Graph()
+        GG.update(H)
+        assert graphs_equal(G, GG)
+        H.update(G)
+        assert graphs_equal(H, G)
+
+        # update nodes only
+        H = self.Graph()
+        H.update(nodes=[3, 4])
+        assert H.nodes ^ {3, 4} == set()
+        assert H.size() == 0
+
+        # update edges only
+        H = self.Graph()
+        H.update(edges=[(3, 4)])
+        assert sorted(H.edges.data()) == [(3, 4, {})]
+        assert H.size() == 1
+
+        # No inputs -> exception
+        with pytest.raises(nx.NetworkXError):
+            nx.Graph().update()
+
+
+class TestEdgeSubgraph:
+    """Unit tests for the :meth:`Graph.edge_subgraph` method."""
+
+    def setup_method(self):
+        # Create a path graph on five nodes.
+        G = nx.path_graph(5)
+        # Add some node, edge, and graph attributes.
+        for i in range(5):
+            G.nodes[i]["name"] = f"node{i}"
+        G.edges[0, 1]["name"] = "edge01"
+        G.edges[3, 4]["name"] = "edge34"
+        G.graph["name"] = "graph"
+        # Get the subgraph induced by the first and last edges.
+        self.G = G
+        self.H = G.edge_subgraph([(0, 1), (3, 4)])
+
+    def test_correct_nodes(self):
+        """Tests that the subgraph has the correct nodes."""
+        assert [0, 1, 3, 4] == sorted(self.H.nodes())
+
+    def test_correct_edges(self):
+        """Tests that the subgraph has the correct edges."""
+        assert [(0, 1, "edge01"), (3, 4, "edge34")] == sorted(self.H.edges(data="name"))
+
+    def test_add_node(self):
+        """Tests that adding a node to the original graph does not
+        affect the nodes of the subgraph.
+
+        """
+        self.G.add_node(5)
+        assert [0, 1, 3, 4] == sorted(self.H.nodes())
+
+    def test_remove_node(self):
+        """Tests that removing a node in the original graph does
+        affect the nodes of the subgraph.
+
+        """
+        self.G.remove_node(0)
+        assert [1, 3, 4] == sorted(self.H.nodes())
+
+    def test_node_attr_dict(self):
+        """Tests that the node attribute dictionary of the two graphs is
+        the same object.
+
+        """
+        for v in self.H:
+            assert self.G.nodes[v] == self.H.nodes[v]
+        # Making a change to G should make a change in H and vice versa.
+        self.G.nodes[0]["name"] = "foo"
+        assert self.G.nodes[0] == self.H.nodes[0]
+        self.H.nodes[1]["name"] = "bar"
+        assert self.G.nodes[1] == self.H.nodes[1]
+
+    def test_edge_attr_dict(self):
+        """Tests that the edge attribute dictionary of the two graphs is
+        the same object.
+
+        """
+        for u, v in self.H.edges():
+            assert self.G.edges[u, v] == self.H.edges[u, v]
+        # Making a change to G should make a change in H and vice versa.
+        self.G.edges[0, 1]["name"] = "foo"
+        assert self.G.edges[0, 1]["name"] == self.H.edges[0, 1]["name"]
+        self.H.edges[3, 4]["name"] = "bar"
+        assert self.G.edges[3, 4]["name"] == self.H.edges[3, 4]["name"]
+
+    def test_graph_attr_dict(self):
+        """Tests that the graph attribute dictionary of the two graphs
+        is the same object.
+
+        """
+        assert self.G.graph is self.H.graph

venv/lib/python3.10/site-packages/networkx/classes/tests/test_graph_historical.py

@@ -0,0 +1,12 @@
+"""Original NetworkX graph tests"""
+import networkx
+import networkx as nx
+
+from .historical_tests import HistoricalTests
+
+
+class TestGraphHistorical(HistoricalTests):
+    @classmethod
+    def setup_class(cls):
+        HistoricalTests.setup_class()
+        cls.G = nx.Graph

venv/lib/python3.10/site-packages/networkx/classes/tests/test_graphviews.py

@@ -0,0 +1,350 @@
+import pytest
+
+import networkx as nx
+from networkx.utils import edges_equal, nodes_equal
+
+# Note: SubGraph views are not tested here. They have their own testing file
+
+
+class TestReverseView:
+    def setup_method(self):
+        self.G = nx.path_graph(9, create_using=nx.DiGraph())
+        self.rv = nx.reverse_view(self.G)
+
+    def test_pickle(self):
+        import pickle
+
+        rv = self.rv
+        prv = pickle.loads(pickle.dumps(rv, -1))
+        assert rv._node == prv._node
+        assert rv._adj == prv._adj
+        assert rv.graph == prv.graph
+
+    def test_contains(self):
+        assert (2, 3) in self.G.edges
+        assert (3, 2) not in self.G.edges
+        assert (2, 3) not in self.rv.edges
+        assert (3, 2) in self.rv.edges
+
+    def test_iter(self):
+        expected = sorted(tuple(reversed(e)) for e in self.G.edges)
+        assert sorted(self.rv.edges) == expected
+
+    def test_exceptions(self):
+        G = nx.Graph()
+        pytest.raises(nx.NetworkXNotImplemented, nx.reverse_view, G)
+
+    def test_subclass(self):
+        class MyGraph(nx.DiGraph):
+            def my_method(self):
+                return "me"
+
+            def to_directed_class(self):
+                return MyGraph()
+
+        M = MyGraph()
+        M.add_edge(1, 2)
+        RM = nx.reverse_view(M)
+        print("RM class", RM.__class__)
+        RMC = RM.copy()
+        print("RMC class", RMC.__class__)
+        print(RMC.edges)
+        assert RMC.has_edge(2, 1)
+        assert RMC.my_method() == "me"
+
+
+class TestMultiReverseView:
+    def setup_method(self):
+        self.G = nx.path_graph(9, create_using=nx.MultiDiGraph())
+        self.G.add_edge(4, 5)
+        self.rv = nx.reverse_view(self.G)
+
+    def test_pickle(self):
+        import pickle
+
+        rv = self.rv
+        prv = pickle.loads(pickle.dumps(rv, -1))
+        assert rv._node == prv._node
+        assert rv._adj == prv._adj
+        assert rv.graph == prv.graph
+
+    def test_contains(self):
+        assert (2, 3, 0) in self.G.edges
+        assert (3, 2, 0) not in self.G.edges
+        assert (2, 3, 0) not in self.rv.edges
+        assert (3, 2, 0) in self.rv.edges
+        assert (5, 4, 1) in self.rv.edges
+        assert (4, 5, 1) not in self.rv.edges
+
+    def test_iter(self):
+        expected = sorted((v, u, k) for u, v, k in self.G.edges)
+        assert sorted(self.rv.edges) == expected
+
+    def test_exceptions(self):
+        MG = nx.MultiGraph(self.G)
+        pytest.raises(nx.NetworkXNotImplemented, nx.reverse_view, MG)
+
+
+def test_generic_multitype():
+    nxg = nx.graphviews
+    G = nx.DiGraph([(1, 2)])
+    with pytest.raises(nx.NetworkXError):
+        nxg.generic_graph_view(G, create_using=nx.MultiGraph)
+    G = nx.MultiDiGraph([(1, 2)])
+    with pytest.raises(nx.NetworkXError):
+        nxg.generic_graph_view(G, create_using=nx.DiGraph)
+
+
+class TestToDirected:
+    def setup_method(self):
+        self.G = nx.path_graph(9)
+        self.dv = nx.to_directed(self.G)
+        self.MG = nx.path_graph(9, create_using=nx.MultiGraph())
+        self.Mdv = nx.to_directed(self.MG)
+
+    def test_directed(self):
+        assert not self.G.is_directed()
+        assert self.dv.is_directed()
+
+    def test_already_directed(self):
+        dd = nx.to_directed(self.dv)
+        Mdd = nx.to_directed(self.Mdv)
+        assert edges_equal(dd.edges, self.dv.edges)
+        assert edges_equal(Mdd.edges, self.Mdv.edges)
+
+    def test_pickle(self):
+        import pickle
+
+        dv = self.dv
+        pdv = pickle.loads(pickle.dumps(dv, -1))
+        assert dv._node == pdv._node
+        assert dv._succ == pdv._succ
+        assert dv._pred == pdv._pred
+        assert dv.graph == pdv.graph
+
+    def test_contains(self):
+        assert (2, 3) in self.G.edges
+        assert (3, 2) in self.G.edges
+        assert (2, 3) in self.dv.edges
+        assert (3, 2) in self.dv.edges
+
+    def test_iter(self):
+        revd = [tuple(reversed(e)) for e in self.G.edges]
+        expected = sorted(list(self.G.edges) + revd)
+        assert sorted(self.dv.edges) == expected
+
+
+class TestToUndirected:
+    def setup_method(self):
+        self.DG = nx.path_graph(9, create_using=nx.DiGraph())
+        self.uv = nx.to_undirected(self.DG)
+        self.MDG = nx.path_graph(9, create_using=nx.MultiDiGraph())
+        self.Muv = nx.to_undirected(self.MDG)
+
+    def test_directed(self):
+        assert self.DG.is_directed()
+        assert not self.uv.is_directed()
+
+    def test_already_directed(self):
+        uu = nx.to_undirected(self.uv)
+        Muu = nx.to_undirected(self.Muv)
+        assert edges_equal(uu.edges, self.uv.edges)
+        assert edges_equal(Muu.edges, self.Muv.edges)
+
+    def test_pickle(self):
+        import pickle
+
+        uv = self.uv
+        puv = pickle.loads(pickle.dumps(uv, -1))
+        assert uv._node == puv._node
+        assert uv._adj == puv._adj
+        assert uv.graph == puv.graph
+        assert hasattr(uv, "_graph")
+
+    def test_contains(self):
+        assert (2, 3) in self.DG.edges
+        assert (3, 2) not in self.DG.edges
+        assert (2, 3) in self.uv.edges
+        assert (3, 2) in self.uv.edges
+
+    def test_iter(self):
+        expected = sorted(self.DG.edges)
+        assert sorted(self.uv.edges) == expected
+
+
+class TestChainsOfViews:
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9)
+        cls.DG = nx.path_graph(9, create_using=nx.DiGraph())
+        cls.MG = nx.path_graph(9, create_using=nx.MultiGraph())
+        cls.MDG = nx.path_graph(9, create_using=nx.MultiDiGraph())
+        cls.Gv = nx.to_undirected(cls.DG)
+        cls.DGv = nx.to_directed(cls.G)
+        cls.MGv = nx.to_undirected(cls.MDG)
+        cls.MDGv = nx.to_directed(cls.MG)
+        cls.Rv = cls.DG.reverse()
+        cls.MRv = cls.MDG.reverse()
+        cls.graphs = [
+            cls.G,
+            cls.DG,
+            cls.MG,
+            cls.MDG,
+            cls.Gv,
+            cls.DGv,
+            cls.MGv,
+            cls.MDGv,
+            cls.Rv,
+            cls.MRv,
+        ]
+        for G in cls.graphs:
+            G.edges, G.nodes, G.degree
+
+    def test_pickle(self):
+        import pickle
+
+        for G in self.graphs:
+            H = pickle.loads(pickle.dumps(G, -1))
+            assert edges_equal(H.edges, G.edges)
+            assert nodes_equal(H.nodes, G.nodes)
+
+    def test_subgraph_of_subgraph(self):
+        SGv = nx.subgraph(self.G, range(3, 7))
+        SDGv = nx.subgraph(self.DG, range(3, 7))
+        SMGv = nx.subgraph(self.MG, range(3, 7))
+        SMDGv = nx.subgraph(self.MDG, range(3, 7))
+        for G in self.graphs + [SGv, SDGv, SMGv, SMDGv]:
+            SG = nx.induced_subgraph(G, [4, 5, 6])
+            assert list(SG) == [4, 5, 6]
+            SSG = SG.subgraph([6, 7])
+            assert list(SSG) == [6]
+            # subgraph-subgraph chain is short-cut in base class method
+            assert SSG._graph is G
+
+    def test_restricted_induced_subgraph_chains(self):
+        """Test subgraph chains that both restrict and show nodes/edges.
+
+        A restricted_view subgraph should allow induced subgraphs using
+        G.subgraph that automagically without a chain (meaning the result
+        is a subgraph view of the original graph not a subgraph-of-subgraph.
+        """
+        hide_nodes = [3, 4, 5]
+        hide_edges = [(6, 7)]
+        RG = nx.restricted_view(self.G, hide_nodes, hide_edges)
+        nodes = [4, 5, 6, 7, 8]
+        SG = nx.induced_subgraph(RG, nodes)
+        SSG = RG.subgraph(nodes)
+        assert RG._graph is self.G
+        assert SSG._graph is self.G
+        assert SG._graph is RG
+        assert edges_equal(SG.edges, SSG.edges)
+        # should be same as morphing the graph
+        CG = self.G.copy()
+        CG.remove_nodes_from(hide_nodes)
+        CG.remove_edges_from(hide_edges)
+        assert edges_equal(CG.edges(nodes), SSG.edges)
+        CG.remove_nodes_from([0, 1, 2, 3])
+        assert edges_equal(CG.edges, SSG.edges)
+        # switch order: subgraph first, then restricted view
+        SSSG = self.G.subgraph(nodes)
+        RSG = nx.restricted_view(SSSG, hide_nodes, hide_edges)
+        assert RSG._graph is not self.G
+        assert edges_equal(RSG.edges, CG.edges)
+
+    def test_subgraph_copy(self):
+        for origG in self.graphs:
+            G = nx.Graph(origG)
+            SG = G.subgraph([4, 5, 6])
+            H = SG.copy()
+            assert type(G) == type(H)
+
+    def test_subgraph_todirected(self):
+        SG = nx.induced_subgraph(self.G, [4, 5, 6])
+        SSG = SG.to_directed()
+        assert sorted(SSG) == [4, 5, 6]
+        assert sorted(SSG.edges) == [(4, 5), (5, 4), (5, 6), (6, 5)]
+
+    def test_subgraph_toundirected(self):
+        SG = nx.induced_subgraph(self.G, [4, 5, 6])
+        SSG = SG.to_undirected()
+        assert list(SSG) == [4, 5, 6]
+        assert sorted(SSG.edges) == [(4, 5), (5, 6)]
+
+    def test_reverse_subgraph_toundirected(self):
+        G = self.DG.reverse(copy=False)
+        SG = G.subgraph([4, 5, 6])
+        SSG = SG.to_undirected()
+        assert list(SSG) == [4, 5, 6]
+        assert sorted(SSG.edges) == [(4, 5), (5, 6)]
+
+    def test_reverse_reverse_copy(self):
+        G = self.DG.reverse(copy=False)
+        H = G.reverse(copy=True)
+        assert H.nodes == self.DG.nodes
+        assert H.edges == self.DG.edges
+        G = self.MDG.reverse(copy=False)
+        H = G.reverse(copy=True)
+        assert H.nodes == self.MDG.nodes
+        assert H.edges == self.MDG.edges
+
+    def test_subgraph_edgesubgraph_toundirected(self):
+        G = self.G.copy()
+        SG = G.subgraph([4, 5, 6])
+        SSG = SG.edge_subgraph([(4, 5), (5, 4)])
+        USSG = SSG.to_undirected()
+        assert list(USSG) == [4, 5]
+        assert sorted(USSG.edges) == [(4, 5)]
+
+    def test_copy_subgraph(self):
+        G = self.G.copy()
+        SG = G.subgraph([4, 5, 6])
+        CSG = SG.copy(as_view=True)
+        DCSG = SG.copy(as_view=False)
+        assert hasattr(CSG, "_graph")  # is a view
+        assert not hasattr(DCSG, "_graph")  # not a view
+
+    def test_copy_disubgraph(self):
+        G = self.DG.copy()
+        SG = G.subgraph([4, 5, 6])
+        CSG = SG.copy(as_view=True)
+        DCSG = SG.copy(as_view=False)
+        assert hasattr(CSG, "_graph")  # is a view
+        assert not hasattr(DCSG, "_graph")  # not a view
+
+    def test_copy_multidisubgraph(self):
+        G = self.MDG.copy()
+        SG = G.subgraph([4, 5, 6])
+        CSG = SG.copy(as_view=True)
+        DCSG = SG.copy(as_view=False)
+        assert hasattr(CSG, "_graph")  # is a view
+        assert not hasattr(DCSG, "_graph")  # not a view
+
+    def test_copy_multisubgraph(self):
+        G = self.MG.copy()
+        SG = G.subgraph([4, 5, 6])
+        CSG = SG.copy(as_view=True)
+        DCSG = SG.copy(as_view=False)
+        assert hasattr(CSG, "_graph")  # is a view
+        assert not hasattr(DCSG, "_graph")  # not a view
+
+    def test_copy_of_view(self):
+        G = nx.MultiGraph(self.MGv)
+        assert G.__class__.__name__ == "MultiGraph"
+        G = G.copy(as_view=True)
+        assert G.__class__.__name__ == "MultiGraph"
+
+    def test_subclass(self):
+        class MyGraph(nx.DiGraph):
+            def my_method(self):
+                return "me"
+
+            def to_directed_class(self):
+                return MyGraph()
+
+        for origG in self.graphs:
+            G = MyGraph(origG)
+            SG = G.subgraph([4, 5, 6])
+            H = SG.copy()
+            assert SG.my_method() == "me"
+            assert H.my_method() == "me"
+            assert 3 not in H or 3 in SG

venv/lib/python3.10/site-packages/networkx/classes/tests/test_multidigraph.py

@@ -0,0 +1,459 @@
+from collections import UserDict
+
+import pytest
+
+import networkx as nx
+from networkx.utils import edges_equal
+
+from .test_multigraph import BaseMultiGraphTester
+from .test_multigraph import TestEdgeSubgraph as _TestMultiGraphEdgeSubgraph
+from .test_multigraph import TestMultiGraph as _TestMultiGraph
+
+
+class BaseMultiDiGraphTester(BaseMultiGraphTester):
+    def test_edges(self):
+        G = self.K3
+        edges = [(0, 1), (0, 2), (1, 0), (1, 2), (2, 0), (2, 1)]
+        assert sorted(G.edges()) == edges
+        assert sorted(G.edges(0)) == [(0, 1), (0, 2)]
+        pytest.raises((KeyError, nx.NetworkXError), G.edges, -1)
+
+    def test_edges_data(self):
+        G = self.K3
+        edges = [(0, 1, {}), (0, 2, {}), (1, 0, {}), (1, 2, {}), (2, 0, {}), (2, 1, {})]
+        assert sorted(G.edges(data=True)) == edges
+        assert sorted(G.edges(0, data=True)) == [(0, 1, {}), (0, 2, {})]
+        pytest.raises((KeyError, nx.NetworkXError), G.neighbors, -1)
+
+    def test_edges_multi(self):
+        G = self.K3
+        assert sorted(G.edges()) == [(0, 1), (0, 2), (1, 0), (1, 2), (2, 0), (2, 1)]
+        assert sorted(G.edges(0)) == [(0, 1), (0, 2)]
+        G.add_edge(0, 1)
+        assert sorted(G.edges()) == [
+            (0, 1),
+            (0, 1),
+            (0, 2),
+            (1, 0),
+            (1, 2),
+            (2, 0),
+            (2, 1),
+        ]
+
+    def test_out_edges(self):
+        G = self.K3
+        assert sorted(G.out_edges()) == [(0, 1), (0, 2), (1, 0), (1, 2), (2, 0), (2, 1)]
+        assert sorted(G.out_edges(0)) == [(0, 1), (0, 2)]
+        pytest.raises((KeyError, nx.NetworkXError), G.out_edges, -1)
+        assert sorted(G.out_edges(0, keys=True)) == [(0, 1, 0), (0, 2, 0)]
+
+    def test_out_edges_multi(self):
+        G = self.K3
+        assert sorted(G.out_edges()) == [(0, 1), (0, 2), (1, 0), (1, 2), (2, 0), (2, 1)]
+        assert sorted(G.out_edges(0)) == [(0, 1), (0, 2)]
+        G.add_edge(0, 1, 2)
+        assert sorted(G.out_edges()) == [
+            (0, 1),
+            (0, 1),
+            (0, 2),
+            (1, 0),
+            (1, 2),
+            (2, 0),
+            (2, 1),
+        ]
+
+    def test_out_edges_data(self):
+        G = self.K3
+        assert sorted(G.edges(0, data=True)) == [(0, 1, {}), (0, 2, {})]
+        G.remove_edge(0, 1)
+        G.add_edge(0, 1, data=1)
+        assert sorted(G.edges(0, data=True)) == [(0, 1, {"data": 1}), (0, 2, {})]
+        assert sorted(G.edges(0, data="data")) == [(0, 1, 1), (0, 2, None)]
+        assert sorted(G.edges(0, data="data", default=-1)) == [(0, 1, 1), (0, 2, -1)]
+
+    def test_in_edges(self):
+        G = self.K3
+        assert sorted(G.in_edges()) == [(0, 1), (0, 2), (1, 0), (1, 2), (2, 0), (2, 1)]
+        assert sorted(G.in_edges(0)) == [(1, 0), (2, 0)]
+        pytest.raises((KeyError, nx.NetworkXError), G.in_edges, -1)
+        G.add_edge(0, 1, 2)
+        assert sorted(G.in_edges()) == [
+            (0, 1),
+            (0, 1),
+            (0, 2),
+            (1, 0),
+            (1, 2),
+            (2, 0),
+            (2, 1),
+        ]
+        assert sorted(G.in_edges(0, keys=True)) == [(1, 0, 0), (2, 0, 0)]
+
+    def test_in_edges_no_keys(self):
+        G = self.K3
+        assert sorted(G.in_edges()) == [(0, 1), (0, 2), (1, 0), (1, 2), (2, 0), (2, 1)]
+        assert sorted(G.in_edges(0)) == [(1, 0), (2, 0)]
+        G.add_edge(0, 1, 2)
+        assert sorted(G.in_edges()) == [
+            (0, 1),
+            (0, 1),
+            (0, 2),
+            (1, 0),
+            (1, 2),
+            (2, 0),
+            (2, 1),
+        ]
+
+        assert sorted(G.in_edges(data=True, keys=False)) == [
+            (0, 1, {}),
+            (0, 1, {}),
+            (0, 2, {}),
+            (1, 0, {}),
+            (1, 2, {}),
+            (2, 0, {}),
+            (2, 1, {}),
+        ]
+
+    def test_in_edges_data(self):
+        G = self.K3
+        assert sorted(G.in_edges(0, data=True)) == [(1, 0, {}), (2, 0, {})]
+        G.remove_edge(1, 0)
+        G.add_edge(1, 0, data=1)
+        assert sorted(G.in_edges(0, data=True)) == [(1, 0, {"data": 1}), (2, 0, {})]
+        assert sorted(G.in_edges(0, data="data")) == [(1, 0, 1), (2, 0, None)]
+        assert sorted(G.in_edges(0, data="data", default=-1)) == [(1, 0, 1), (2, 0, -1)]
+
+    def is_shallow(self, H, G):
+        # graph
+        assert G.graph["foo"] == H.graph["foo"]
+        G.graph["foo"].append(1)
+        assert G.graph["foo"] == H.graph["foo"]
+        # node
+        assert G.nodes[0]["foo"] == H.nodes[0]["foo"]
+        G.nodes[0]["foo"].append(1)
+        assert G.nodes[0]["foo"] == H.nodes[0]["foo"]
+        # edge
+        assert G[1][2][0]["foo"] == H[1][2][0]["foo"]
+        G[1][2][0]["foo"].append(1)
+        assert G[1][2][0]["foo"] == H[1][2][0]["foo"]
+
+    def is_deep(self, H, G):
+        # graph
+        assert G.graph["foo"] == H.graph["foo"]
+        G.graph["foo"].append(1)
+        assert G.graph["foo"] != H.graph["foo"]
+        # node
+        assert G.nodes[0]["foo"] == H.nodes[0]["foo"]
+        G.nodes[0]["foo"].append(1)
+        assert G.nodes[0]["foo"] != H.nodes[0]["foo"]
+        # edge
+        assert G[1][2][0]["foo"] == H[1][2][0]["foo"]
+        G[1][2][0]["foo"].append(1)
+        assert G[1][2][0]["foo"] != H[1][2][0]["foo"]
+
+    def test_to_undirected(self):
+        # MultiDiGraph -> MultiGraph changes number of edges so it is
+        # not a copy operation... use is_shallow, not is_shallow_copy
+        G = self.K3
+        self.add_attributes(G)
+        H = nx.MultiGraph(G)
+        # self.is_shallow(H,G)
+        # the result is traversal order dependent so we
+        # can't use the is_shallow() test here.
+        try:
+            assert edges_equal(H.edges(), [(0, 1), (1, 2), (2, 0)])
+        except AssertionError:
+            assert edges_equal(H.edges(), [(0, 1), (1, 2), (1, 2), (2, 0)])
+        H = G.to_undirected()
+        self.is_deep(H, G)
+
+    def test_has_successor(self):
+        G = self.K3
+        assert G.has_successor(0, 1)
+        assert not G.has_successor(0, -1)
+
+    def test_successors(self):
+        G = self.K3
+        assert sorted(G.successors(0)) == [1, 2]
+        pytest.raises((KeyError, nx.NetworkXError), G.successors, -1)
+
+    def test_has_predecessor(self):
+        G = self.K3
+        assert G.has_predecessor(0, 1)
+        assert not G.has_predecessor(0, -1)
+
+    def test_predecessors(self):
+        G = self.K3
+        assert sorted(G.predecessors(0)) == [1, 2]
+        pytest.raises((KeyError, nx.NetworkXError), G.predecessors, -1)
+
+    def test_degree(self):
+        G = self.K3
+        assert sorted(G.degree()) == [(0, 4), (1, 4), (2, 4)]
+        assert dict(G.degree()) == {0: 4, 1: 4, 2: 4}
+        assert G.degree(0) == 4
+        assert list(G.degree(iter([0]))) == [(0, 4)]
+        G.add_edge(0, 1, weight=0.3, other=1.2)
+        assert sorted(G.degree(weight="weight")) == [(0, 4.3), (1, 4.3), (2, 4)]
+        assert sorted(G.degree(weight="other")) == [(0, 5.2), (1, 5.2), (2, 4)]
+
+    def test_in_degree(self):
+        G = self.K3
+        assert sorted(G.in_degree()) == [(0, 2), (1, 2), (2, 2)]
+        assert dict(G.in_degree()) == {0: 2, 1: 2, 2: 2}
+        assert G.in_degree(0) == 2
+        assert list(G.in_degree(iter([0]))) == [(0, 2)]
+        assert G.in_degree(0, weight="weight") == 2
+
+    def test_out_degree(self):
+        G = self.K3
+        assert sorted(G.out_degree()) == [(0, 2), (1, 2), (2, 2)]
+        assert dict(G.out_degree()) == {0: 2, 1: 2, 2: 2}
+        assert G.out_degree(0) == 2
+        assert list(G.out_degree(iter([0]))) == [(0, 2)]
+        assert G.out_degree(0, weight="weight") == 2
+
+    def test_size(self):
+        G = self.K3
+        assert G.size() == 6
+        assert G.number_of_edges() == 6
+        G.add_edge(0, 1, weight=0.3, other=1.2)
+        assert round(G.size(weight="weight"), 2) == 6.3
+        assert round(G.size(weight="other"), 2) == 7.2
+
+    def test_to_undirected_reciprocal(self):
+        G = self.Graph()
+        G.add_edge(1, 2)
+        assert G.to_undirected().has_edge(1, 2)
+        assert not G.to_undirected(reciprocal=True).has_edge(1, 2)
+        G.add_edge(2, 1)
+        assert G.to_undirected(reciprocal=True).has_edge(1, 2)
+
+    def test_reverse_copy(self):
+        G = nx.MultiDiGraph([(0, 1), (0, 1)])
+        R = G.reverse()
+        assert sorted(R.edges()) == [(1, 0), (1, 0)]
+        R.remove_edge(1, 0)
+        assert sorted(R.edges()) == [(1, 0)]
+        assert sorted(G.edges()) == [(0, 1), (0, 1)]
+
+    def test_reverse_nocopy(self):
+        G = nx.MultiDiGraph([(0, 1), (0, 1)])
+        R = G.reverse(copy=False)
+        assert sorted(R.edges()) == [(1, 0), (1, 0)]
+        pytest.raises(nx.NetworkXError, R.remove_edge, 1, 0)
+
+    def test_di_attributes_cached(self):
+        G = self.K3.copy()
+        assert id(G.in_edges) == id(G.in_edges)
+        assert id(G.out_edges) == id(G.out_edges)
+        assert id(G.in_degree) == id(G.in_degree)
+        assert id(G.out_degree) == id(G.out_degree)
+        assert id(G.succ) == id(G.succ)
+        assert id(G.pred) == id(G.pred)
+
+
+class TestMultiDiGraph(BaseMultiDiGraphTester, _TestMultiGraph):
+    def setup_method(self):
+        self.Graph = nx.MultiDiGraph
+        # build K3
+        self.k3edges = [(0, 1), (0, 2), (1, 2)]
+        self.k3nodes = [0, 1, 2]
+        self.K3 = self.Graph()
+        self.K3._succ = {0: {}, 1: {}, 2: {}}
+        # K3._adj is synced with K3._succ
+        self.K3._pred = {0: {}, 1: {}, 2: {}}
+        for u in self.k3nodes:
+            for v in self.k3nodes:
+                if u == v:
+                    continue
+                d = {0: {}}
+                self.K3._succ[u][v] = d
+                self.K3._pred[v][u] = d
+        self.K3._node = {}
+        self.K3._node[0] = {}
+        self.K3._node[1] = {}
+        self.K3._node[2] = {}
+
+    def test_add_edge(self):
+        G = self.Graph()
+        G.add_edge(0, 1)
+        assert G._adj == {0: {1: {0: {}}}, 1: {}}
+        assert G._succ == {0: {1: {0: {}}}, 1: {}}
+        assert G._pred == {0: {}, 1: {0: {0: {}}}}
+        G = self.Graph()
+        G.add_edge(*(0, 1))
+        assert G._adj == {0: {1: {0: {}}}, 1: {}}
+        assert G._succ == {0: {1: {0: {}}}, 1: {}}
+        assert G._pred == {0: {}, 1: {0: {0: {}}}}
+        with pytest.raises(ValueError, match="None cannot be a node"):
+            G.add_edge(None, 3)
+
+    def test_add_edges_from(self):
+        G = self.Graph()
+        G.add_edges_from([(0, 1), (0, 1, {"weight": 3})])
+        assert G._adj == {0: {1: {0: {}, 1: {"weight": 3}}}, 1: {}}
+        assert G._succ == {0: {1: {0: {}, 1: {"weight": 3}}}, 1: {}}
+        assert G._pred == {0: {}, 1: {0: {0: {}, 1: {"weight": 3}}}}
+
+        G.add_edges_from([(0, 1), (0, 1, {"weight": 3})], weight=2)
+        assert G._succ == {
+            0: {1: {0: {}, 1: {"weight": 3}, 2: {"weight": 2}, 3: {"weight": 3}}},
+            1: {},
+        }
+        assert G._pred == {
+            0: {},
+            1: {0: {0: {}, 1: {"weight": 3}, 2: {"weight": 2}, 3: {"weight": 3}}},
+        }
+
+        G = self.Graph()
+        edges = [
+            (0, 1, {"weight": 3}),
+            (0, 1, (("weight", 2),)),
+            (0, 1, 5),
+            (0, 1, "s"),
+        ]
+        G.add_edges_from(edges)
+        keydict = {0: {"weight": 3}, 1: {"weight": 2}, 5: {}, "s": {}}
+        assert G._succ == {0: {1: keydict}, 1: {}}
+        assert G._pred == {1: {0: keydict}, 0: {}}
+
+        # too few in tuple
+        pytest.raises(nx.NetworkXError, G.add_edges_from, [(0,)])
+        # too many in tuple
+        pytest.raises(nx.NetworkXError, G.add_edges_from, [(0, 1, 2, 3, 4)])
+        # not a tuple
+        pytest.raises(TypeError, G.add_edges_from, [0])
+        with pytest.raises(ValueError, match="None cannot be a node"):
+            G.add_edges_from([(None, 3), (3, 2)])
+
+    def test_remove_edge(self):
+        G = self.K3
+        G.remove_edge(0, 1)
+        assert G._succ == {
+            0: {2: {0: {}}},
+            1: {0: {0: {}}, 2: {0: {}}},
+            2: {0: {0: {}}, 1: {0: {}}},
+        }
+        assert G._pred == {
+            0: {1: {0: {}}, 2: {0: {}}},
+            1: {2: {0: {}}},
+            2: {0: {0: {}}, 1: {0: {}}},
+        }
+        pytest.raises((KeyError, nx.NetworkXError), G.remove_edge, -1, 0)
+        pytest.raises((KeyError, nx.NetworkXError), G.remove_edge, 0, 2, key=1)
+
+    def test_remove_multiedge(self):
+        G = self.K3
+        G.add_edge(0, 1, key="parallel edge")
+        G.remove_edge(0, 1, key="parallel edge")
+        assert G._adj == {
+            0: {1: {0: {}}, 2: {0: {}}},
+            1: {0: {0: {}}, 2: {0: {}}},
+            2: {0: {0: {}}, 1: {0: {}}},
+        }
+
+        assert G._succ == {
+            0: {1: {0: {}}, 2: {0: {}}},
+            1: {0: {0: {}}, 2: {0: {}}},
+            2: {0: {0: {}}, 1: {0: {}}},
+        }
+
+        assert G._pred == {
+            0: {1: {0: {}}, 2: {0: {}}},
+            1: {0: {0: {}}, 2: {0: {}}},
+            2: {0: {0: {}}, 1: {0: {}}},
+        }
+        G.remove_edge(0, 1)
+        assert G._succ == {
+            0: {2: {0: {}}},
+            1: {0: {0: {}}, 2: {0: {}}},
+            2: {0: {0: {}}, 1: {0: {}}},
+        }
+        assert G._pred == {
+            0: {1: {0: {}}, 2: {0: {}}},
+            1: {2: {0: {}}},
+            2: {0: {0: {}}, 1: {0: {}}},
+        }
+        pytest.raises((KeyError, nx.NetworkXError), G.remove_edge, -1, 0)
+
+    def test_remove_edges_from(self):
+        G = self.K3
+        G.remove_edges_from([(0, 1)])
+        assert G._succ == {
+            0: {2: {0: {}}},
+            1: {0: {0: {}}, 2: {0: {}}},
+            2: {0: {0: {}}, 1: {0: {}}},
+        }
+        assert G._pred == {
+            0: {1: {0: {}}, 2: {0: {}}},
+            1: {2: {0: {}}},
+            2: {0: {0: {}}, 1: {0: {}}},
+        }
+        G.remove_edges_from([(0, 0)])  # silent fail
+
+
+class TestEdgeSubgraph(_TestMultiGraphEdgeSubgraph):
+    """Unit tests for the :meth:`MultiDiGraph.edge_subgraph` method."""
+
+    def setup_method(self):
+        # Create a quadruply-linked path graph on five nodes.
+        G = nx.MultiDiGraph()
+        nx.add_path(G, range(5))
+        nx.add_path(G, range(5))
+        nx.add_path(G, reversed(range(5)))
+        nx.add_path(G, reversed(range(5)))
+        # Add some node, edge, and graph attributes.
+        for i in range(5):
+            G.nodes[i]["name"] = f"node{i}"
+        G.adj[0][1][0]["name"] = "edge010"
+        G.adj[0][1][1]["name"] = "edge011"
+        G.adj[3][4][0]["name"] = "edge340"
+        G.adj[3][4][1]["name"] = "edge341"
+        G.graph["name"] = "graph"
+        # Get the subgraph induced by one of the first edges and one of
+        # the last edges.
+        self.G = G
+        self.H = G.edge_subgraph([(0, 1, 0), (3, 4, 1)])
+
+
+class CustomDictClass(UserDict):
+    pass
+
+
+class MultiDiGraphSubClass(nx.MultiDiGraph):
+    node_dict_factory = CustomDictClass  # type: ignore[assignment]
+    node_attr_dict_factory = CustomDictClass  # type: ignore[assignment]
+    adjlist_outer_dict_factory = CustomDictClass  # type: ignore[assignment]
+    adjlist_inner_dict_factory = CustomDictClass  # type: ignore[assignment]
+    edge_key_dict_factory = CustomDictClass  # type: ignore[assignment]
+    edge_attr_dict_factory = CustomDictClass  # type: ignore[assignment]
+    graph_attr_dict_factory = CustomDictClass  # type: ignore[assignment]
+
+
+class TestMultiDiGraphSubclass(TestMultiDiGraph):
+    def setup_method(self):
+        self.Graph = MultiDiGraphSubClass
+        # build K3
+        self.k3edges = [(0, 1), (0, 2), (1, 2)]
+        self.k3nodes = [0, 1, 2]
+        self.K3 = self.Graph()
+        self.K3._succ = self.K3.adjlist_outer_dict_factory(
+            {
+                0: self.K3.adjlist_inner_dict_factory(),
+                1: self.K3.adjlist_inner_dict_factory(),
+                2: self.K3.adjlist_inner_dict_factory(),
+            }
+        )
+        # K3._adj is synced with K3._succ
+        self.K3._pred = {0: {}, 1: {}, 2: {}}
+        for u in self.k3nodes:
+            for v in self.k3nodes:
+                if u == v:
+                    continue
+                d = {0: {}}
+                self.K3._succ[u][v] = d
+                self.K3._pred[v][u] = d
+        self.K3._node = self.K3.node_dict_factory()
+        self.K3._node[0] = self.K3.node_attr_dict_factory()
+        self.K3._node[1] = self.K3.node_attr_dict_factory()
+        self.K3._node[2] = self.K3.node_attr_dict_factory()

venv/lib/python3.10/site-packages/networkx/classes/tests/test_multigraph.py

@@ -0,0 +1,528 @@
+from collections import UserDict
+
+import pytest
+
+import networkx as nx
+from networkx.utils import edges_equal
+
+from .test_graph import BaseAttrGraphTester
+from .test_graph import TestGraph as _TestGraph
+
+
+class BaseMultiGraphTester(BaseAttrGraphTester):
+    def test_has_edge(self):
+        G = self.K3
+        assert G.has_edge(0, 1)
+        assert not G.has_edge(0, -1)
+        assert G.has_edge(0, 1, 0)
+        assert not G.has_edge(0, 1, 1)
+
+    def test_get_edge_data(self):
+        G = self.K3
+        assert G.get_edge_data(0, 1) == {0: {}}
+        assert G[0][1] == {0: {}}
+        assert G[0][1][0] == {}
+        assert G.get_edge_data(10, 20) is None
+        assert G.get_edge_data(0, 1, 0) == {}
+
+    def test_adjacency(self):
+        G = self.K3
+        assert dict(G.adjacency()) == {
+            0: {1: {0: {}}, 2: {0: {}}},
+            1: {0: {0: {}}, 2: {0: {}}},
+            2: {0: {0: {}}, 1: {0: {}}},
+        }
+
+    def deepcopy_edge_attr(self, H, G):
+        assert G[1][2][0]["foo"] == H[1][2][0]["foo"]
+        G[1][2][0]["foo"].append(1)
+        assert G[1][2][0]["foo"] != H[1][2][0]["foo"]
+
+    def shallow_copy_edge_attr(self, H, G):
+        assert G[1][2][0]["foo"] == H[1][2][0]["foo"]
+        G[1][2][0]["foo"].append(1)
+        assert G[1][2][0]["foo"] == H[1][2][0]["foo"]
+
+    def graphs_equal(self, H, G):
+        assert G._adj == H._adj
+        assert G._node == H._node
+        assert G.graph == H.graph
+        assert G.name == H.name
+        if not G.is_directed() and not H.is_directed():
+            assert H._adj[1][2][0] is H._adj[2][1][0]
+            assert G._adj[1][2][0] is G._adj[2][1][0]
+        else:  # at least one is directed
+            if not G.is_directed():
+                G._pred = G._adj
+                G._succ = G._adj
+            if not H.is_directed():
+                H._pred = H._adj
+                H._succ = H._adj
+            assert G._pred == H._pred
+            assert G._succ == H._succ
+            assert H._succ[1][2][0] is H._pred[2][1][0]
+            assert G._succ[1][2][0] is G._pred[2][1][0]
+
+    def same_attrdict(self, H, G):
+        # same attrdict in the edgedata
+        old_foo = H[1][2][0]["foo"]
+        H.adj[1][2][0]["foo"] = "baz"
+        assert G._adj == H._adj
+        H.adj[1][2][0]["foo"] = old_foo
+        assert G._adj == H._adj
+
+        old_foo = H.nodes[0]["foo"]
+        H.nodes[0]["foo"] = "baz"
+        assert G._node == H._node
+        H.nodes[0]["foo"] = old_foo
+        assert G._node == H._node
+
+    def different_attrdict(self, H, G):
+        # used by graph_equal_but_different
+        old_foo = H[1][2][0]["foo"]
+        H.adj[1][2][0]["foo"] = "baz"
+        assert G._adj != H._adj
+        H.adj[1][2][0]["foo"] = old_foo
+        assert G._adj == H._adj
+
+        old_foo = H.nodes[0]["foo"]
+        H.nodes[0]["foo"] = "baz"
+        assert G._node != H._node
+        H.nodes[0]["foo"] = old_foo
+        assert G._node == H._node
+
+    def test_to_undirected(self):
+        G = self.K3
+        self.add_attributes(G)
+        H = nx.MultiGraph(G)
+        self.is_shallow_copy(H, G)
+        H = G.to_undirected()
+        self.is_deepcopy(H, G)
+
+    def test_to_directed(self):
+        G = self.K3
+        self.add_attributes(G)
+        H = nx.MultiDiGraph(G)
+        self.is_shallow_copy(H, G)
+        H = G.to_directed()
+        self.is_deepcopy(H, G)
+
+    def test_number_of_edges_selfloops(self):
+        G = self.K3
+        G.add_edge(0, 0)
+        G.add_edge(0, 0)
+        G.add_edge(0, 0, key="parallel edge")
+        G.remove_edge(0, 0, key="parallel edge")
+        assert G.number_of_edges(0, 0) == 2
+        G.remove_edge(0, 0)
+        assert G.number_of_edges(0, 0) == 1
+
+    def test_edge_lookup(self):
+        G = self.Graph()
+        G.add_edge(1, 2, foo="bar")
+        G.add_edge(1, 2, "key", foo="biz")
+        assert edges_equal(G.edges[1, 2, 0], {"foo": "bar"})
+        assert edges_equal(G.edges[1, 2, "key"], {"foo": "biz"})
+
+    def test_edge_attr(self):
+        G = self.Graph()
+        G.add_edge(1, 2, key="k1", foo="bar")
+        G.add_edge(1, 2, key="k2", foo="baz")
+        assert isinstance(G.get_edge_data(1, 2), G.edge_key_dict_factory)
+        assert all(
+            isinstance(d, G.edge_attr_dict_factory) for u, v, d in G.edges(data=True)
+        )
+        assert edges_equal(
+            G.edges(keys=True, data=True),
+            [(1, 2, "k1", {"foo": "bar"}), (1, 2, "k2", {"foo": "baz"})],
+        )
+        assert edges_equal(
+            G.edges(keys=True, data="foo"), [(1, 2, "k1", "bar"), (1, 2, "k2", "baz")]
+        )
+
+    def test_edge_attr4(self):
+        G = self.Graph()
+        G.add_edge(1, 2, key=0, data=7, spam="bar", bar="foo")
+        assert edges_equal(
+            G.edges(data=True), [(1, 2, {"data": 7, "spam": "bar", "bar": "foo"})]
+        )
+        G[1][2][0]["data"] = 10  # OK to set data like this
+        assert edges_equal(
+            G.edges(data=True), [(1, 2, {"data": 10, "spam": "bar", "bar": "foo"})]
+        )
+
+        G.adj[1][2][0]["data"] = 20
+        assert edges_equal(
+            G.edges(data=True), [(1, 2, {"data": 20, "spam": "bar", "bar": "foo"})]
+        )
+        G.edges[1, 2, 0]["data"] = 21  # another spelling, "edge"
+        assert edges_equal(
+            G.edges(data=True), [(1, 2, {"data": 21, "spam": "bar", "bar": "foo"})]
+        )
+        G.adj[1][2][0]["listdata"] = [20, 200]
+        G.adj[1][2][0]["weight"] = 20
+        assert edges_equal(
+            G.edges(data=True),
+            [
+                (
+                    1,
+                    2,
+                    {
+                        "data": 21,
+                        "spam": "bar",
+                        "bar": "foo",
+                        "listdata": [20, 200],
+                        "weight": 20,
+                    },
+                )
+            ],
+        )
+
+
+class TestMultiGraph(BaseMultiGraphTester, _TestGraph):
+    def setup_method(self):
+        self.Graph = nx.MultiGraph
+        # build K3
+        ed1, ed2, ed3 = ({0: {}}, {0: {}}, {0: {}})
+        self.k3adj = {0: {1: ed1, 2: ed2}, 1: {0: ed1, 2: ed3}, 2: {0: ed2, 1: ed3}}
+        self.k3edges = [(0, 1), (0, 2), (1, 2)]
+        self.k3nodes = [0, 1, 2]
+        self.K3 = self.Graph()
+        self.K3._adj = self.k3adj
+        self.K3._node = {}
+        self.K3._node[0] = {}
+        self.K3._node[1] = {}
+        self.K3._node[2] = {}
+
+    def test_data_input(self):
+        G = self.Graph({1: [2], 2: [1]}, name="test")
+        assert G.name == "test"
+        expected = [(1, {2: {0: {}}}), (2, {1: {0: {}}})]
+        assert sorted(G.adj.items()) == expected
+
+    def test_data_multigraph_input(self):
+        # standard case with edge keys and edge data
+        edata0 = {"w": 200, "s": "foo"}
+        edata1 = {"w": 201, "s": "bar"}
+        keydict = {0: edata0, 1: edata1}
+        dododod = {"a": {"b": keydict}}
+
+        multiple_edge = [("a", "b", 0, edata0), ("a", "b", 1, edata1)]
+        single_edge = [("a", "b", 0, keydict)]
+
+        G = self.Graph(dododod, multigraph_input=True)
+        assert list(G.edges(keys=True, data=True)) == multiple_edge
+        G = self.Graph(dododod, multigraph_input=None)
+        assert list(G.edges(keys=True, data=True)) == multiple_edge
+        G = self.Graph(dododod, multigraph_input=False)
+        assert list(G.edges(keys=True, data=True)) == single_edge
+
+        # test round-trip to_dict_of_dict and MultiGraph constructor
+        G = self.Graph(dododod, multigraph_input=True)
+        H = self.Graph(nx.to_dict_of_dicts(G))
+        assert nx.is_isomorphic(G, H) is True  # test that default is True
+        for mgi in [True, False]:
+            H = self.Graph(nx.to_dict_of_dicts(G), multigraph_input=mgi)
+            assert nx.is_isomorphic(G, H) == mgi
+
+    # Set up cases for when incoming_graph_data is not multigraph_input
+    etraits = {"w": 200, "s": "foo"}
+    egraphics = {"color": "blue", "shape": "box"}
+    edata = {"traits": etraits, "graphics": egraphics}
+    dodod1 = {"a": {"b": edata}}
+    dodod2 = {"a": {"b": etraits}}
+    dodod3 = {"a": {"b": {"traits": etraits, "s": "foo"}}}
+    dol = {"a": ["b"]}
+
+    multiple_edge = [("a", "b", "traits", etraits), ("a", "b", "graphics", egraphics)]
+    single_edge = [("a", "b", 0, {})]  # type: ignore[var-annotated]
+    single_edge1 = [("a", "b", 0, edata)]
+    single_edge2 = [("a", "b", 0, etraits)]
+    single_edge3 = [("a", "b", 0, {"traits": etraits, "s": "foo"})]
+
+    cases = [  # (dod, mgi, edges)
+        (dodod1, True, multiple_edge),
+        (dodod1, False, single_edge1),
+        (dodod2, False, single_edge2),
+        (dodod3, False, single_edge3),
+        (dol, False, single_edge),
+    ]
+
+    @pytest.mark.parametrize("dod, mgi, edges", cases)
+    def test_non_multigraph_input(self, dod, mgi, edges):
+        G = self.Graph(dod, multigraph_input=mgi)
+        assert list(G.edges(keys=True, data=True)) == edges
+        G = nx.to_networkx_graph(dod, create_using=self.Graph, multigraph_input=mgi)
+        assert list(G.edges(keys=True, data=True)) == edges
+
+    mgi_none_cases = [
+        (dodod1, multiple_edge),
+        (dodod2, single_edge2),
+        (dodod3, single_edge3),
+    ]
+
+    @pytest.mark.parametrize("dod, edges", mgi_none_cases)
+    def test_non_multigraph_input_mgi_none(self, dod, edges):
+        # test constructor without to_networkx_graph for mgi=None
+        G = self.Graph(dod)
+        assert list(G.edges(keys=True, data=True)) == edges
+
+    raise_cases = [dodod2, dodod3, dol]
+
+    @pytest.mark.parametrize("dod", raise_cases)
+    def test_non_multigraph_input_raise(self, dod):
+        # cases where NetworkXError is raised
+        pytest.raises(nx.NetworkXError, self.Graph, dod, multigraph_input=True)
+        pytest.raises(
+            nx.NetworkXError,
+            nx.to_networkx_graph,
+            dod,
+            create_using=self.Graph,
+            multigraph_input=True,
+        )
+
+    def test_getitem(self):
+        G = self.K3
+        assert G[0] == {1: {0: {}}, 2: {0: {}}}
+        with pytest.raises(KeyError):
+            G.__getitem__("j")
+        with pytest.raises(TypeError):
+            G.__getitem__(["A"])
+
+    def test_remove_node(self):
+        G = self.K3
+        G.remove_node(0)
+        assert G.adj == {1: {2: {0: {}}}, 2: {1: {0: {}}}}
+        with pytest.raises(nx.NetworkXError):
+            G.remove_node(-1)
+
+    def test_add_edge(self):
+        G = self.Graph()
+        G.add_edge(0, 1)
+        assert G.adj == {0: {1: {0: {}}}, 1: {0: {0: {}}}}
+        G = self.Graph()
+        G.add_edge(*(0, 1))
+        assert G.adj == {0: {1: {0: {}}}, 1: {0: {0: {}}}}
+        G = self.Graph()
+        with pytest.raises(ValueError):
+            G.add_edge(None, "anything")
+
+    def test_add_edge_conflicting_key(self):
+        G = self.Graph()
+        G.add_edge(0, 1, key=1)
+        G.add_edge(0, 1)
+        assert G.number_of_edges() == 2
+        G = self.Graph()
+        G.add_edges_from([(0, 1, 1, {})])
+        G.add_edges_from([(0, 1)])
+        assert G.number_of_edges() == 2
+
+    def test_add_edges_from(self):
+        G = self.Graph()
+        G.add_edges_from([(0, 1), (0, 1, {"weight": 3})])
+        assert G.adj == {
+            0: {1: {0: {}, 1: {"weight": 3}}},
+            1: {0: {0: {}, 1: {"weight": 3}}},
+        }
+        G.add_edges_from([(0, 1), (0, 1, {"weight": 3})], weight=2)
+        assert G.adj == {
+            0: {1: {0: {}, 1: {"weight": 3}, 2: {"weight": 2}, 3: {"weight": 3}}},
+            1: {0: {0: {}, 1: {"weight": 3}, 2: {"weight": 2}, 3: {"weight": 3}}},
+        }
+        G = self.Graph()
+        edges = [
+            (0, 1, {"weight": 3}),
+            (0, 1, (("weight", 2),)),
+            (0, 1, 5),
+            (0, 1, "s"),
+        ]
+        G.add_edges_from(edges)
+        keydict = {0: {"weight": 3}, 1: {"weight": 2}, 5: {}, "s": {}}
+        assert G._adj == {0: {1: keydict}, 1: {0: keydict}}
+
+        # too few in tuple
+        with pytest.raises(nx.NetworkXError):
+            G.add_edges_from([(0,)])
+        # too many in tuple
+        with pytest.raises(nx.NetworkXError):
+            G.add_edges_from([(0, 1, 2, 3, 4)])
+        # not a tuple
+        with pytest.raises(TypeError):
+            G.add_edges_from([0])
+
+    def test_multigraph_add_edges_from_four_tuple_misordered(self):
+        """add_edges_from expects 4-tuples of the format (u, v, key, data_dict).
+
+        Ensure 4-tuples of form (u, v, data_dict, key) raise exception.
+        """
+        G = nx.MultiGraph()
+        with pytest.raises(TypeError):
+            # key/data values flipped in 4-tuple
+            G.add_edges_from([(0, 1, {"color": "red"}, 0)])
+
+    def test_remove_edge(self):
+        G = self.K3
+        G.remove_edge(0, 1)
+        assert G.adj == {0: {2: {0: {}}}, 1: {2: {0: {}}}, 2: {0: {0: {}}, 1: {0: {}}}}
+
+        with pytest.raises(nx.NetworkXError):
+            G.remove_edge(-1, 0)
+        with pytest.raises(nx.NetworkXError):
+            G.remove_edge(0, 2, key=1)
+
+    def test_remove_edges_from(self):
+        G = self.K3.copy()
+        G.remove_edges_from([(0, 1)])
+        kd = {0: {}}
+        assert G.adj == {0: {2: kd}, 1: {2: kd}, 2: {0: kd, 1: kd}}
+        G.remove_edges_from([(0, 0)])  # silent fail
+        self.K3.add_edge(0, 1)
+        G = self.K3.copy()
+        G.remove_edges_from(list(G.edges(data=True, keys=True)))
+        assert G.adj == {0: {}, 1: {}, 2: {}}
+        G = self.K3.copy()
+        G.remove_edges_from(list(G.edges(data=False, keys=True)))
+        assert G.adj == {0: {}, 1: {}, 2: {}}
+        G = self.K3.copy()
+        G.remove_edges_from(list(G.edges(data=False, keys=False)))
+        assert G.adj == {0: {}, 1: {}, 2: {}}
+        G = self.K3.copy()
+        G.remove_edges_from([(0, 1, 0), (0, 2, 0, {}), (1, 2)])
+        assert G.adj == {0: {1: {1: {}}}, 1: {0: {1: {}}}, 2: {}}
+
+    def test_remove_multiedge(self):
+        G = self.K3
+        G.add_edge(0, 1, key="parallel edge")
+        G.remove_edge(0, 1, key="parallel edge")
+        assert G.adj == {
+            0: {1: {0: {}}, 2: {0: {}}},
+            1: {0: {0: {}}, 2: {0: {}}},
+            2: {0: {0: {}}, 1: {0: {}}},
+        }
+        G.remove_edge(0, 1)
+        kd = {0: {}}
+        assert G.adj == {0: {2: kd}, 1: {2: kd}, 2: {0: kd, 1: kd}}
+        with pytest.raises(nx.NetworkXError):
+            G.remove_edge(-1, 0)
+
+
+class TestEdgeSubgraph:
+    """Unit tests for the :meth:`MultiGraph.edge_subgraph` method."""
+
+    def setup_method(self):
+        # Create a doubly-linked path graph on five nodes.
+        G = nx.MultiGraph()
+        nx.add_path(G, range(5))
+        nx.add_path(G, range(5))
+        # Add some node, edge, and graph attributes.
+        for i in range(5):
+            G.nodes[i]["name"] = f"node{i}"
+        G.adj[0][1][0]["name"] = "edge010"
+        G.adj[0][1][1]["name"] = "edge011"
+        G.adj[3][4][0]["name"] = "edge340"
+        G.adj[3][4][1]["name"] = "edge341"
+        G.graph["name"] = "graph"
+        # Get the subgraph induced by one of the first edges and one of
+        # the last edges.
+        self.G = G
+        self.H = G.edge_subgraph([(0, 1, 0), (3, 4, 1)])
+
+    def test_correct_nodes(self):
+        """Tests that the subgraph has the correct nodes."""
+        assert [0, 1, 3, 4] == sorted(self.H.nodes())
+
+    def test_correct_edges(self):
+        """Tests that the subgraph has the correct edges."""
+        assert [(0, 1, 0, "edge010"), (3, 4, 1, "edge341")] == sorted(
+            self.H.edges(keys=True, data="name")
+        )
+
+    def test_add_node(self):
+        """Tests that adding a node to the original graph does not
+        affect the nodes of the subgraph.
+
+        """
+        self.G.add_node(5)
+        assert [0, 1, 3, 4] == sorted(self.H.nodes())
+
+    def test_remove_node(self):
+        """Tests that removing a node in the original graph does
+        affect the nodes of the subgraph.
+
+        """
+        self.G.remove_node(0)
+        assert [1, 3, 4] == sorted(self.H.nodes())
+
+    def test_node_attr_dict(self):
+        """Tests that the node attribute dictionary of the two graphs is
+        the same object.
+
+        """
+        for v in self.H:
+            assert self.G.nodes[v] == self.H.nodes[v]
+        # Making a change to G should make a change in H and vice versa.
+        self.G.nodes[0]["name"] = "foo"
+        assert self.G.nodes[0] == self.H.nodes[0]
+        self.H.nodes[1]["name"] = "bar"
+        assert self.G.nodes[1] == self.H.nodes[1]
+
+    def test_edge_attr_dict(self):
+        """Tests that the edge attribute dictionary of the two graphs is
+        the same object.
+
+        """
+        for u, v, k in self.H.edges(keys=True):
+            assert self.G._adj[u][v][k] == self.H._adj[u][v][k]
+        # Making a change to G should make a change in H and vice versa.
+        self.G._adj[0][1][0]["name"] = "foo"
+        assert self.G._adj[0][1][0]["name"] == self.H._adj[0][1][0]["name"]
+        self.H._adj[3][4][1]["name"] = "bar"
+        assert self.G._adj[3][4][1]["name"] == self.H._adj[3][4][1]["name"]
+
+    def test_graph_attr_dict(self):
+        """Tests that the graph attribute dictionary of the two graphs
+        is the same object.
+
+        """
+        assert self.G.graph is self.H.graph
+
+
+class CustomDictClass(UserDict):
+    pass
+
+
+class MultiGraphSubClass(nx.MultiGraph):
+    node_dict_factory = CustomDictClass  # type: ignore[assignment]
+    node_attr_dict_factory = CustomDictClass  # type: ignore[assignment]
+    adjlist_outer_dict_factory = CustomDictClass  # type: ignore[assignment]
+    adjlist_inner_dict_factory = CustomDictClass  # type: ignore[assignment]
+    edge_key_dict_factory = CustomDictClass  # type: ignore[assignment]
+    edge_attr_dict_factory = CustomDictClass  # type: ignore[assignment]
+    graph_attr_dict_factory = CustomDictClass  # type: ignore[assignment]
+
+
+class TestMultiGraphSubclass(TestMultiGraph):
+    def setup_method(self):
+        self.Graph = MultiGraphSubClass
+        # build K3
+        self.k3edges = [(0, 1), (0, 2), (1, 2)]
+        self.k3nodes = [0, 1, 2]
+        self.K3 = self.Graph()
+        self.K3._adj = self.K3.adjlist_outer_dict_factory(
+            {
+                0: self.K3.adjlist_inner_dict_factory(),
+                1: self.K3.adjlist_inner_dict_factory(),
+                2: self.K3.adjlist_inner_dict_factory(),
+            }
+        )
+        self.K3._pred = {0: {}, 1: {}, 2: {}}
+        for u in self.k3nodes:
+            for v in self.k3nodes:
+                if u != v:
+                    d = {0: {}}
+                    self.K3._adj[u][v] = d
+                    self.K3._adj[v][u] = d
+        self.K3._node = self.K3.node_dict_factory()
+        self.K3._node[0] = self.K3.node_attr_dict_factory()
+        self.K3._node[1] = self.K3.node_attr_dict_factory()
+        self.K3._node[2] = self.K3.node_attr_dict_factory()

venv/lib/python3.10/site-packages/networkx/classes/tests/test_reportviews.py

@@ -0,0 +1,1427 @@
+import pickle
+from copy import deepcopy
+
+import pytest
+
+import networkx as nx
+from networkx.classes import reportviews as rv
+from networkx.classes.reportviews import NodeDataView
+
+
+# Nodes
+class TestNodeView:
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9)
+        cls.nv = cls.G.nodes  # NodeView(G)
+
+    def test_pickle(self):
+        import pickle
+
+        nv = self.nv
+        pnv = pickle.loads(pickle.dumps(nv, -1))
+        assert nv == pnv
+        assert nv.__slots__ == pnv.__slots__
+
+    def test_str(self):
+        assert str(self.nv) == "[0, 1, 2, 3, 4, 5, 6, 7, 8]"
+
+    def test_repr(self):
+        assert repr(self.nv) == "NodeView((0, 1, 2, 3, 4, 5, 6, 7, 8))"
+
+    def test_contains(self):
+        G = self.G.copy()
+        nv = G.nodes
+        assert 7 in nv
+        assert 9 not in nv
+        G.remove_node(7)
+        G.add_node(9)
+        assert 7 not in nv
+        assert 9 in nv
+
+    def test_getitem(self):
+        G = self.G.copy()
+        nv = G.nodes
+        G.nodes[3]["foo"] = "bar"
+        assert nv[7] == {}
+        assert nv[3] == {"foo": "bar"}
+        # slicing
+        with pytest.raises(nx.NetworkXError):
+            G.nodes[0:5]
+
+    def test_iter(self):
+        nv = self.nv
+        for i, n in enumerate(nv):
+            assert i == n
+        inv = iter(nv)
+        assert next(inv) == 0
+        assert iter(nv) != nv
+        assert iter(inv) == inv
+        inv2 = iter(nv)
+        next(inv2)
+        assert list(inv) == list(inv2)
+        # odd case where NodeView calls NodeDataView with data=False
+        nnv = nv(data=False)
+        for i, n in enumerate(nnv):
+            assert i == n
+
+    def test_call(self):
+        nodes = self.nv
+        assert nodes is nodes()
+        assert nodes is not nodes(data=True)
+        assert nodes is not nodes(data="weight")
+
+
+class TestNodeDataView:
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9)
+        cls.nv = NodeDataView(cls.G)
+        cls.ndv = cls.G.nodes.data(True)
+        cls.nwv = cls.G.nodes.data("foo")
+
+    def test_viewtype(self):
+        nv = self.G.nodes
+        ndvfalse = nv.data(False)
+        assert nv is ndvfalse
+        assert nv is not self.ndv
+
+    def test_pickle(self):
+        import pickle
+
+        nv = self.nv
+        pnv = pickle.loads(pickle.dumps(nv, -1))
+        assert nv == pnv
+        assert nv.__slots__ == pnv.__slots__
+
+    def test_str(self):
+        msg = str([(n, {}) for n in range(9)])
+        assert str(self.ndv) == msg
+
+    def test_repr(self):
+        expected = "NodeDataView((0, 1, 2, 3, 4, 5, 6, 7, 8))"
+        assert repr(self.nv) == expected
+        expected = (
+            "NodeDataView({0: {}, 1: {}, 2: {}, 3: {}, "
+            + "4: {}, 5: {}, 6: {}, 7: {}, 8: {}})"
+        )
+        assert repr(self.ndv) == expected
+        expected = (
+            "NodeDataView({0: None, 1: None, 2: None, 3: None, 4: None, "
+            + "5: None, 6: None, 7: None, 8: None}, data='foo')"
+        )
+        assert repr(self.nwv) == expected
+
+    def test_contains(self):
+        G = self.G.copy()
+        nv = G.nodes.data()
+        nwv = G.nodes.data("foo")
+        G.nodes[3]["foo"] = "bar"
+        assert (7, {}) in nv
+        assert (3, {"foo": "bar"}) in nv
+        assert (3, "bar") in nwv
+        assert (7, None) in nwv
+        # default
+        nwv_def = G.nodes(data="foo", default="biz")
+        assert (7, "biz") in nwv_def
+        assert (3, "bar") in nwv_def
+
+    def test_getitem(self):
+        G = self.G.copy()
+        nv = G.nodes
+        G.nodes[3]["foo"] = "bar"
+        assert nv[3] == {"foo": "bar"}
+        # default
+        nwv_def = G.nodes(data="foo", default="biz")
+        assert nwv_def[7], "biz"
+        assert nwv_def[3] == "bar"
+        # slicing
+        with pytest.raises(nx.NetworkXError):
+            G.nodes.data()[0:5]
+
+    def test_iter(self):
+        G = self.G.copy()
+        nv = G.nodes.data()
+        ndv = G.nodes.data(True)
+        nwv = G.nodes.data("foo")
+        for i, (n, d) in enumerate(nv):
+            assert i == n
+            assert d == {}
+        inv = iter(nv)
+        assert next(inv) == (0, {})
+        G.nodes[3]["foo"] = "bar"
+        # default
+        for n, d in nv:
+            if n == 3:
+                assert d == {"foo": "bar"}
+            else:
+                assert d == {}
+        # data=True
+        for n, d in ndv:
+            if n == 3:
+                assert d == {"foo": "bar"}
+            else:
+                assert d == {}
+        # data='foo'
+        for n, d in nwv:
+            if n == 3:
+                assert d == "bar"
+            else:
+                assert d is None
+        # data='foo', default=1
+        for n, d in G.nodes.data("foo", default=1):
+            if n == 3:
+                assert d == "bar"
+            else:
+                assert d == 1
+
+
+def test_nodedataview_unhashable():
+    G = nx.path_graph(9)
+    G.nodes[3]["foo"] = "bar"
+    nvs = [G.nodes.data()]
+    nvs.append(G.nodes.data(True))
+    H = G.copy()
+    H.nodes[4]["foo"] = {1, 2, 3}
+    nvs.append(H.nodes.data(True))
+    # raise unhashable
+    for nv in nvs:
+        pytest.raises(TypeError, set, nv)
+        pytest.raises(TypeError, eval, "nv | nv", locals())
+    # no raise... hashable
+    Gn = G.nodes.data(False)
+    set(Gn)
+    Gn | Gn
+    Gn = G.nodes.data("foo")
+    set(Gn)
+    Gn | Gn
+
+
+class TestNodeViewSetOps:
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9)
+        cls.G.nodes[3]["foo"] = "bar"
+        cls.nv = cls.G.nodes
+
+    def n_its(self, nodes):
+        return set(nodes)
+
+    def test_len(self):
+        G = self.G.copy()
+        nv = G.nodes
+        assert len(nv) == 9
+        G.remove_node(7)
+        assert len(nv) == 8
+        G.add_node(9)
+        assert len(nv) == 9
+
+    def test_and(self):
+        # print("G & H nodes:", gnv & hnv)
+        nv = self.nv
+        some_nodes = self.n_its(range(5, 12))
+        assert nv & some_nodes == self.n_its(range(5, 9))
+        assert some_nodes & nv == self.n_its(range(5, 9))
+
+    def test_or(self):
+        # print("G | H nodes:", gnv | hnv)
+        nv = self.nv
+        some_nodes = self.n_its(range(5, 12))
+        assert nv | some_nodes == self.n_its(range(12))
+        assert some_nodes | nv == self.n_its(range(12))
+
+    def test_xor(self):
+        # print("G ^ H nodes:", gnv ^ hnv)
+        nv = self.nv
+        some_nodes = self.n_its(range(5, 12))
+        nodes = {0, 1, 2, 3, 4, 9, 10, 11}
+        assert nv ^ some_nodes == self.n_its(nodes)
+        assert some_nodes ^ nv == self.n_its(nodes)
+
+    def test_sub(self):
+        # print("G - H nodes:", gnv - hnv)
+        nv = self.nv
+        some_nodes = self.n_its(range(5, 12))
+        assert nv - some_nodes == self.n_its(range(5))
+        assert some_nodes - nv == self.n_its(range(9, 12))
+
+
+class TestNodeDataViewSetOps(TestNodeViewSetOps):
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9)
+        cls.G.nodes[3]["foo"] = "bar"
+        cls.nv = cls.G.nodes.data("foo")
+
+    def n_its(self, nodes):
+        return {(node, "bar" if node == 3 else None) for node in nodes}
+
+
+class TestNodeDataViewDefaultSetOps(TestNodeDataViewSetOps):
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9)
+        cls.G.nodes[3]["foo"] = "bar"
+        cls.nv = cls.G.nodes.data("foo", default=1)
+
+    def n_its(self, nodes):
+        return {(node, "bar" if node == 3 else 1) for node in nodes}
+
+
+# Edges Data View
+class TestEdgeDataView:
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9)
+        cls.eview = nx.reportviews.EdgeView
+
+    def test_pickle(self):
+        import pickle
+
+        ev = self.eview(self.G)(data=True)
+        pev = pickle.loads(pickle.dumps(ev, -1))
+        assert list(ev) == list(pev)
+        assert ev.__slots__ == pev.__slots__
+
+    def modify_edge(self, G, e, **kwds):
+        G._adj[e[0]][e[1]].update(kwds)
+
+    def test_str(self):
+        ev = self.eview(self.G)(data=True)
+        rep = str([(n, n + 1, {}) for n in range(8)])
+        assert str(ev) == rep
+
+    def test_repr(self):
+        ev = self.eview(self.G)(data=True)
+        rep = (
+            "EdgeDataView([(0, 1, {}), (1, 2, {}), "
+            + "(2, 3, {}), (3, 4, {}), "
+            + "(4, 5, {}), (5, 6, {}), "
+            + "(6, 7, {}), (7, 8, {})])"
+        )
+        assert repr(ev) == rep
+
+    def test_iterdata(self):
+        G = self.G.copy()
+        evr = self.eview(G)
+        ev = evr(data=True)
+        ev_def = evr(data="foo", default=1)
+
+        for u, v, d in ev:
+            pass
+        assert d == {}
+
+        for u, v, wt in ev_def:
+            pass
+        assert wt == 1
+
+        self.modify_edge(G, (2, 3), foo="bar")
+        for e in ev:
+            assert len(e) == 3
+            if set(e[:2]) == {2, 3}:
+                assert e[2] == {"foo": "bar"}
+                checked = True
+            else:
+                assert e[2] == {}
+        assert checked
+
+        for e in ev_def:
+            assert len(e) == 3
+            if set(e[:2]) == {2, 3}:
+                assert e[2] == "bar"
+                checked_wt = True
+            else:
+                assert e[2] == 1
+        assert checked_wt
+
+    def test_iter(self):
+        evr = self.eview(self.G)
+        ev = evr()
+        for u, v in ev:
+            pass
+        iev = iter(ev)
+        assert next(iev) == (0, 1)
+        assert iter(ev) != ev
+        assert iter(iev) == iev
+
+    def test_contains(self):
+        evr = self.eview(self.G)
+        ev = evr()
+        if self.G.is_directed():
+            assert (1, 2) in ev and (2, 1) not in ev
+        else:
+            assert (1, 2) in ev and (2, 1) in ev
+        assert (1, 4) not in ev
+        assert (1, 90) not in ev
+        assert (90, 1) not in ev
+
+    def test_contains_with_nbunch(self):
+        evr = self.eview(self.G)
+        ev = evr(nbunch=[0, 2])
+        if self.G.is_directed():
+            assert (0, 1) in ev
+            assert (1, 2) not in ev
+            assert (2, 3) in ev
+        else:
+            assert (0, 1) in ev
+            assert (1, 2) in ev
+            assert (2, 3) in ev
+        assert (3, 4) not in ev
+        assert (4, 5) not in ev
+        assert (5, 6) not in ev
+        assert (7, 8) not in ev
+        assert (8, 9) not in ev
+
+    def test_len(self):
+        evr = self.eview(self.G)
+        ev = evr(data="foo")
+        assert len(ev) == 8
+        assert len(evr(1)) == 2
+        assert len(evr([1, 2, 3])) == 4
+
+        assert len(self.G.edges(1)) == 2
+        assert len(self.G.edges()) == 8
+        assert len(self.G.edges) == 8
+
+        H = self.G.copy()
+        H.add_edge(1, 1)
+        assert len(H.edges(1)) == 3
+        assert len(H.edges()) == 9
+        assert len(H.edges) == 9
+
+
+class TestOutEdgeDataView(TestEdgeDataView):
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9, create_using=nx.DiGraph())
+        cls.eview = nx.reportviews.OutEdgeView
+
+    def test_repr(self):
+        ev = self.eview(self.G)(data=True)
+        rep = (
+            "OutEdgeDataView([(0, 1, {}), (1, 2, {}), "
+            + "(2, 3, {}), (3, 4, {}), "
+            + "(4, 5, {}), (5, 6, {}), "
+            + "(6, 7, {}), (7, 8, {})])"
+        )
+        assert repr(ev) == rep
+
+    def test_len(self):
+        evr = self.eview(self.G)
+        ev = evr(data="foo")
+        assert len(ev) == 8
+        assert len(evr(1)) == 1
+        assert len(evr([1, 2, 3])) == 3
+
+        assert len(self.G.edges(1)) == 1
+        assert len(self.G.edges()) == 8
+        assert len(self.G.edges) == 8
+
+        H = self.G.copy()
+        H.add_edge(1, 1)
+        assert len(H.edges(1)) == 2
+        assert len(H.edges()) == 9
+        assert len(H.edges) == 9
+
+    def test_contains_with_nbunch(self):
+        evr = self.eview(self.G)
+        ev = evr(nbunch=[0, 2])
+        assert (0, 1) in ev
+        assert (1, 2) not in ev
+        assert (2, 3) in ev
+        assert (3, 4) not in ev
+        assert (4, 5) not in ev
+        assert (5, 6) not in ev
+        assert (7, 8) not in ev
+        assert (8, 9) not in ev
+
+
+class TestInEdgeDataView(TestOutEdgeDataView):
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9, create_using=nx.DiGraph())
+        cls.eview = nx.reportviews.InEdgeView
+
+    def test_repr(self):
+        ev = self.eview(self.G)(data=True)
+        rep = (
+            "InEdgeDataView([(0, 1, {}), (1, 2, {}), "
+            + "(2, 3, {}), (3, 4, {}), "
+            + "(4, 5, {}), (5, 6, {}), "
+            + "(6, 7, {}), (7, 8, {})])"
+        )
+        assert repr(ev) == rep
+
+    def test_contains_with_nbunch(self):
+        evr = self.eview(self.G)
+        ev = evr(nbunch=[0, 2])
+        assert (0, 1) not in ev
+        assert (1, 2) in ev
+        assert (2, 3) not in ev
+        assert (3, 4) not in ev
+        assert (4, 5) not in ev
+        assert (5, 6) not in ev
+        assert (7, 8) not in ev
+        assert (8, 9) not in ev
+
+
+class TestMultiEdgeDataView(TestEdgeDataView):
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9, create_using=nx.MultiGraph())
+        cls.eview = nx.reportviews.MultiEdgeView
+
+    def modify_edge(self, G, e, **kwds):
+        G._adj[e[0]][e[1]][0].update(kwds)
+
+    def test_repr(self):
+        ev = self.eview(self.G)(data=True)
+        rep = (
+            "MultiEdgeDataView([(0, 1, {}), (1, 2, {}), "
+            + "(2, 3, {}), (3, 4, {}), "
+            + "(4, 5, {}), (5, 6, {}), "
+            + "(6, 7, {}), (7, 8, {})])"
+        )
+        assert repr(ev) == rep
+
+    def test_contains_with_nbunch(self):
+        evr = self.eview(self.G)
+        ev = evr(nbunch=[0, 2])
+        assert (0, 1) in ev
+        assert (1, 2) in ev
+        assert (2, 3) in ev
+        assert (3, 4) not in ev
+        assert (4, 5) not in ev
+        assert (5, 6) not in ev
+        assert (7, 8) not in ev
+        assert (8, 9) not in ev
+
+
+class TestOutMultiEdgeDataView(TestOutEdgeDataView):
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9, create_using=nx.MultiDiGraph())
+        cls.eview = nx.reportviews.OutMultiEdgeView
+
+    def modify_edge(self, G, e, **kwds):
+        G._adj[e[0]][e[1]][0].update(kwds)
+
+    def test_repr(self):
+        ev = self.eview(self.G)(data=True)
+        rep = (
+            "OutMultiEdgeDataView([(0, 1, {}), (1, 2, {}), "
+            + "(2, 3, {}), (3, 4, {}), "
+            + "(4, 5, {}), (5, 6, {}), "
+            + "(6, 7, {}), (7, 8, {})])"
+        )
+        assert repr(ev) == rep
+
+    def test_contains_with_nbunch(self):
+        evr = self.eview(self.G)
+        ev = evr(nbunch=[0, 2])
+        assert (0, 1) in ev
+        assert (1, 2) not in ev
+        assert (2, 3) in ev
+        assert (3, 4) not in ev
+        assert (4, 5) not in ev
+        assert (5, 6) not in ev
+        assert (7, 8) not in ev
+        assert (8, 9) not in ev
+
+
+class TestInMultiEdgeDataView(TestOutMultiEdgeDataView):
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9, create_using=nx.MultiDiGraph())
+        cls.eview = nx.reportviews.InMultiEdgeView
+
+    def test_repr(self):
+        ev = self.eview(self.G)(data=True)
+        rep = (
+            "InMultiEdgeDataView([(0, 1, {}), (1, 2, {}), "
+            + "(2, 3, {}), (3, 4, {}), "
+            + "(4, 5, {}), (5, 6, {}), "
+            + "(6, 7, {}), (7, 8, {})])"
+        )
+        assert repr(ev) == rep
+
+    def test_contains_with_nbunch(self):
+        evr = self.eview(self.G)
+        ev = evr(nbunch=[0, 2])
+        assert (0, 1) not in ev
+        assert (1, 2) in ev
+        assert (2, 3) not in ev
+        assert (3, 4) not in ev
+        assert (4, 5) not in ev
+        assert (5, 6) not in ev
+        assert (7, 8) not in ev
+        assert (8, 9) not in ev
+
+
+# Edge Views
+class TestEdgeView:
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9)
+        cls.eview = nx.reportviews.EdgeView
+
+    def test_pickle(self):
+        import pickle
+
+        ev = self.eview(self.G)
+        pev = pickle.loads(pickle.dumps(ev, -1))
+        assert ev == pev
+        assert ev.__slots__ == pev.__slots__
+
+    def modify_edge(self, G, e, **kwds):
+        G._adj[e[0]][e[1]].update(kwds)
+
+    def test_str(self):
+        ev = self.eview(self.G)
+        rep = str([(n, n + 1) for n in range(8)])
+        assert str(ev) == rep
+
+    def test_repr(self):
+        ev = self.eview(self.G)
+        rep = (
+            "EdgeView([(0, 1), (1, 2), (2, 3), (3, 4), "
+            + "(4, 5), (5, 6), (6, 7), (7, 8)])"
+        )
+        assert repr(ev) == rep
+
+    def test_getitem(self):
+        G = self.G.copy()
+        ev = G.edges
+        G.edges[0, 1]["foo"] = "bar"
+        assert ev[0, 1] == {"foo": "bar"}
+
+        # slicing
+        with pytest.raises(nx.NetworkXError, match=".*does not support slicing"):
+            G.edges[0:5]
+
+        # Invalid edge
+        with pytest.raises(KeyError, match=r".*edge.*is not in the graph."):
+            G.edges[0, 9]
+
+    def test_call(self):
+        ev = self.eview(self.G)
+        assert id(ev) == id(ev())
+        assert id(ev) == id(ev(data=False))
+        assert id(ev) != id(ev(data=True))
+        assert id(ev) != id(ev(nbunch=1))
+
+    def test_data(self):
+        ev = self.eview(self.G)
+        assert id(ev) != id(ev.data())
+        assert id(ev) == id(ev.data(data=False))
+        assert id(ev) != id(ev.data(data=True))
+        assert id(ev) != id(ev.data(nbunch=1))
+
+    def test_iter(self):
+        ev = self.eview(self.G)
+        for u, v in ev:
+            pass
+        iev = iter(ev)
+        assert next(iev) == (0, 1)
+        assert iter(ev) != ev
+        assert iter(iev) == iev
+
+    def test_contains(self):
+        ev = self.eview(self.G)
+        edv = ev()
+        if self.G.is_directed():
+            assert (1, 2) in ev and (2, 1) not in ev
+            assert (1, 2) in edv and (2, 1) not in edv
+        else:
+            assert (1, 2) in ev and (2, 1) in ev
+            assert (1, 2) in edv and (2, 1) in edv
+        assert (1, 4) not in ev
+        assert (1, 4) not in edv
+        # edge not in graph
+        assert (1, 90) not in ev
+        assert (90, 1) not in ev
+        assert (1, 90) not in edv
+        assert (90, 1) not in edv
+
+    def test_contains_with_nbunch(self):
+        ev = self.eview(self.G)
+        evn = ev(nbunch=[0, 2])
+        assert (0, 1) in evn
+        assert (1, 2) in evn
+        assert (2, 3) in evn
+        assert (3, 4) not in evn
+        assert (4, 5) not in evn
+        assert (5, 6) not in evn
+        assert (7, 8) not in evn
+        assert (8, 9) not in evn
+
+    def test_len(self):
+        ev = self.eview(self.G)
+        num_ed = 9 if self.G.is_multigraph() else 8
+        assert len(ev) == num_ed
+
+        H = self.G.copy()
+        H.add_edge(1, 1)
+        assert len(H.edges(1)) == 3 + H.is_multigraph() - H.is_directed()
+        assert len(H.edges()) == num_ed + 1
+        assert len(H.edges) == num_ed + 1
+
+    def test_and(self):
+        # print("G & H edges:", gnv & hnv)
+        ev = self.eview(self.G)
+        some_edges = {(0, 1), (1, 0), (0, 2)}
+        if self.G.is_directed():
+            assert some_edges & ev, {(0, 1)}
+            assert ev & some_edges, {(0, 1)}
+        else:
+            assert ev & some_edges == {(0, 1), (1, 0)}
+            assert some_edges & ev == {(0, 1), (1, 0)}
+        return
+
+    def test_or(self):
+        # print("G | H edges:", gnv | hnv)
+        ev = self.eview(self.G)
+        some_edges = {(0, 1), (1, 0), (0, 2)}
+        result1 = {(n, n + 1) for n in range(8)}
+        result1.update(some_edges)
+        result2 = {(n + 1, n) for n in range(8)}
+        result2.update(some_edges)
+        assert (ev | some_edges) in (result1, result2)
+        assert (some_edges | ev) in (result1, result2)
+
+    def test_xor(self):
+        # print("G ^ H edges:", gnv ^ hnv)
+        ev = self.eview(self.G)
+        some_edges = {(0, 1), (1, 0), (0, 2)}
+        if self.G.is_directed():
+            result = {(n, n + 1) for n in range(1, 8)}
+            result.update({(1, 0), (0, 2)})
+            assert ev ^ some_edges == result
+        else:
+            result = {(n, n + 1) for n in range(1, 8)}
+            result.update({(0, 2)})
+            assert ev ^ some_edges == result
+        return
+
+    def test_sub(self):
+        # print("G - H edges:", gnv - hnv)
+        ev = self.eview(self.G)
+        some_edges = {(0, 1), (1, 0), (0, 2)}
+        result = {(n, n + 1) for n in range(8)}
+        result.remove((0, 1))
+        assert ev - some_edges, result
+
+
+class TestOutEdgeView(TestEdgeView):
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9, nx.DiGraph())
+        cls.eview = nx.reportviews.OutEdgeView
+
+    def test_repr(self):
+        ev = self.eview(self.G)
+        rep = (
+            "OutEdgeView([(0, 1), (1, 2), (2, 3), (3, 4), "
+            + "(4, 5), (5, 6), (6, 7), (7, 8)])"
+        )
+        assert repr(ev) == rep
+
+    def test_contains_with_nbunch(self):
+        ev = self.eview(self.G)
+        evn = ev(nbunch=[0, 2])
+        assert (0, 1) in evn
+        assert (1, 2) not in evn
+        assert (2, 3) in evn
+        assert (3, 4) not in evn
+        assert (4, 5) not in evn
+        assert (5, 6) not in evn
+        assert (7, 8) not in evn
+        assert (8, 9) not in evn
+
+
+class TestInEdgeView(TestEdgeView):
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9, nx.DiGraph())
+        cls.eview = nx.reportviews.InEdgeView
+
+    def test_repr(self):
+        ev = self.eview(self.G)
+        rep = (
+            "InEdgeView([(0, 1), (1, 2), (2, 3), (3, 4), "
+            + "(4, 5), (5, 6), (6, 7), (7, 8)])"
+        )
+        assert repr(ev) == rep
+
+    def test_contains_with_nbunch(self):
+        ev = self.eview(self.G)
+        evn = ev(nbunch=[0, 2])
+        assert (0, 1) not in evn
+        assert (1, 2) in evn
+        assert (2, 3) not in evn
+        assert (3, 4) not in evn
+        assert (4, 5) not in evn
+        assert (5, 6) not in evn
+        assert (7, 8) not in evn
+        assert (8, 9) not in evn
+
+
+class TestMultiEdgeView(TestEdgeView):
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9, nx.MultiGraph())
+        cls.G.add_edge(1, 2, key=3, foo="bar")
+        cls.eview = nx.reportviews.MultiEdgeView
+
+    def modify_edge(self, G, e, **kwds):
+        if len(e) == 2:
+            e = e + (0,)
+        G._adj[e[0]][e[1]][e[2]].update(kwds)
+
+    def test_str(self):
+        ev = self.eview(self.G)
+        replist = [(n, n + 1, 0) for n in range(8)]
+        replist.insert(2, (1, 2, 3))
+        rep = str(replist)
+        assert str(ev) == rep
+
+    def test_getitem(self):
+        G = self.G.copy()
+        ev = G.edges
+        G.edges[0, 1, 0]["foo"] = "bar"
+        assert ev[0, 1, 0] == {"foo": "bar"}
+
+        # slicing
+        with pytest.raises(nx.NetworkXError):
+            G.edges[0:5]
+
+    def test_repr(self):
+        ev = self.eview(self.G)
+        rep = (
+            "MultiEdgeView([(0, 1, 0), (1, 2, 0), (1, 2, 3), (2, 3, 0), "
+            + "(3, 4, 0), (4, 5, 0), (5, 6, 0), (6, 7, 0), (7, 8, 0)])"
+        )
+        assert repr(ev) == rep
+
+    def test_call(self):
+        ev = self.eview(self.G)
+        assert id(ev) == id(ev(keys=True))
+        assert id(ev) == id(ev(data=False, keys=True))
+        assert id(ev) != id(ev(keys=False))
+        assert id(ev) != id(ev(data=True))
+        assert id(ev) != id(ev(nbunch=1))
+
+    def test_data(self):
+        ev = self.eview(self.G)
+        assert id(ev) != id(ev.data())
+        assert id(ev) == id(ev.data(data=False, keys=True))
+        assert id(ev) != id(ev.data(keys=False))
+        assert id(ev) != id(ev.data(data=True))
+        assert id(ev) != id(ev.data(nbunch=1))
+
+    def test_iter(self):
+        ev = self.eview(self.G)
+        for u, v, k in ev:
+            pass
+        iev = iter(ev)
+        assert next(iev) == (0, 1, 0)
+        assert iter(ev) != ev
+        assert iter(iev) == iev
+
+    def test_iterkeys(self):
+        G = self.G
+        evr = self.eview(G)
+        ev = evr(keys=True)
+        for u, v, k in ev:
+            pass
+        assert k == 0
+        ev = evr(keys=True, data="foo", default=1)
+        for u, v, k, wt in ev:
+            pass
+        assert wt == 1
+
+        self.modify_edge(G, (2, 3, 0), foo="bar")
+        ev = evr(keys=True, data=True)
+        for e in ev:
+            assert len(e) == 4
+            print("edge:", e)
+            if set(e[:2]) == {2, 3}:
+                print(self.G._adj[2][3])
+                assert e[2] == 0
+                assert e[3] == {"foo": "bar"}
+                checked = True
+            elif set(e[:3]) == {1, 2, 3}:
+                assert e[2] == 3
+                assert e[3] == {"foo": "bar"}
+                checked_multi = True
+            else:
+                assert e[2] == 0
+                assert e[3] == {}
+        assert checked
+        assert checked_multi
+        ev = evr(keys=True, data="foo", default=1)
+        for e in ev:
+            if set(e[:2]) == {1, 2} and e[2] == 3:
+                assert e[3] == "bar"
+            if set(e[:2]) == {1, 2} and e[2] == 0:
+                assert e[3] == 1
+            if set(e[:2]) == {2, 3}:
+                assert e[2] == 0
+                assert e[3] == "bar"
+                assert len(e) == 4
+                checked_wt = True
+        assert checked_wt
+        ev = evr(keys=True)
+        for e in ev:
+            assert len(e) == 3
+        elist = sorted([(i, i + 1, 0) for i in range(8)] + [(1, 2, 3)])
+        assert sorted(ev) == elist
+        # test that the keyword arguments are passed correctly
+        ev = evr((1, 2), "foo", keys=True, default=1)
+        with pytest.raises(TypeError):
+            evr((1, 2), "foo", True, 1)
+        with pytest.raises(TypeError):
+            evr((1, 2), "foo", True, default=1)
+        for e in ev:
+            if set(e[:2]) == {1, 2}:
+                assert e[2] in {0, 3}
+                if e[2] == 3:
+                    assert e[3] == "bar"
+                else:  # e[2] == 0
+                    assert e[3] == 1
+        if G.is_directed():
+            assert len(list(ev)) == 3
+        else:
+            assert len(list(ev)) == 4
+
+    def test_or(self):
+        # print("G | H edges:", gnv | hnv)
+        ev = self.eview(self.G)
+        some_edges = {(0, 1, 0), (1, 0, 0), (0, 2, 0)}
+        result = {(n, n + 1, 0) for n in range(8)}
+        result.update(some_edges)
+        result.update({(1, 2, 3)})
+        assert ev | some_edges == result
+        assert some_edges | ev == result
+
+    def test_sub(self):
+        # print("G - H edges:", gnv - hnv)
+        ev = self.eview(self.G)
+        some_edges = {(0, 1, 0), (1, 0, 0), (0, 2, 0)}
+        result = {(n, n + 1, 0) for n in range(8)}
+        result.remove((0, 1, 0))
+        result.update({(1, 2, 3)})
+        assert ev - some_edges, result
+        assert some_edges - ev, result
+
+    def test_xor(self):
+        # print("G ^ H edges:", gnv ^ hnv)
+        ev = self.eview(self.G)
+        some_edges = {(0, 1, 0), (1, 0, 0), (0, 2, 0)}
+        if self.G.is_directed():
+            result = {(n, n + 1, 0) for n in range(1, 8)}
+            result.update({(1, 0, 0), (0, 2, 0), (1, 2, 3)})
+            assert ev ^ some_edges == result
+            assert some_edges ^ ev == result
+        else:
+            result = {(n, n + 1, 0) for n in range(1, 8)}
+            result.update({(0, 2, 0), (1, 2, 3)})
+            assert ev ^ some_edges == result
+            assert some_edges ^ ev == result
+
+    def test_and(self):
+        # print("G & H edges:", gnv & hnv)
+        ev = self.eview(self.G)
+        some_edges = {(0, 1, 0), (1, 0, 0), (0, 2, 0)}
+        if self.G.is_directed():
+            assert ev & some_edges == {(0, 1, 0)}
+            assert some_edges & ev == {(0, 1, 0)}
+        else:
+            assert ev & some_edges == {(0, 1, 0), (1, 0, 0)}
+            assert some_edges & ev == {(0, 1, 0), (1, 0, 0)}
+
+    def test_contains_with_nbunch(self):
+        ev = self.eview(self.G)
+        evn = ev(nbunch=[0, 2])
+        assert (0, 1) in evn
+        assert (1, 2) in evn
+        assert (2, 3) in evn
+        assert (3, 4) not in evn
+        assert (4, 5) not in evn
+        assert (5, 6) not in evn
+        assert (7, 8) not in evn
+        assert (8, 9) not in evn
+
+
+class TestOutMultiEdgeView(TestMultiEdgeView):
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9, nx.MultiDiGraph())
+        cls.G.add_edge(1, 2, key=3, foo="bar")
+        cls.eview = nx.reportviews.OutMultiEdgeView
+
+    def modify_edge(self, G, e, **kwds):
+        if len(e) == 2:
+            e = e + (0,)
+        G._adj[e[0]][e[1]][e[2]].update(kwds)
+
+    def test_repr(self):
+        ev = self.eview(self.G)
+        rep = (
+            "OutMultiEdgeView([(0, 1, 0), (1, 2, 0), (1, 2, 3), (2, 3, 0),"
+            + " (3, 4, 0), (4, 5, 0), (5, 6, 0), (6, 7, 0), (7, 8, 0)])"
+        )
+        assert repr(ev) == rep
+
+    def test_contains_with_nbunch(self):
+        ev = self.eview(self.G)
+        evn = ev(nbunch=[0, 2])
+        assert (0, 1) in evn
+        assert (1, 2) not in evn
+        assert (2, 3) in evn
+        assert (3, 4) not in evn
+        assert (4, 5) not in evn
+        assert (5, 6) not in evn
+        assert (7, 8) not in evn
+        assert (8, 9) not in evn
+
+
+class TestInMultiEdgeView(TestMultiEdgeView):
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9, nx.MultiDiGraph())
+        cls.G.add_edge(1, 2, key=3, foo="bar")
+        cls.eview = nx.reportviews.InMultiEdgeView
+
+    def modify_edge(self, G, e, **kwds):
+        if len(e) == 2:
+            e = e + (0,)
+        G._adj[e[0]][e[1]][e[2]].update(kwds)
+
+    def test_repr(self):
+        ev = self.eview(self.G)
+        rep = (
+            "InMultiEdgeView([(0, 1, 0), (1, 2, 0), (1, 2, 3), (2, 3, 0), "
+            + "(3, 4, 0), (4, 5, 0), (5, 6, 0), (6, 7, 0), (7, 8, 0)])"
+        )
+        assert repr(ev) == rep
+
+    def test_contains_with_nbunch(self):
+        ev = self.eview(self.G)
+        evn = ev(nbunch=[0, 2])
+        assert (0, 1) not in evn
+        assert (1, 2) in evn
+        assert (2, 3) not in evn
+        assert (3, 4) not in evn
+        assert (4, 5) not in evn
+        assert (5, 6) not in evn
+        assert (7, 8) not in evn
+        assert (8, 9) not in evn
+
+
+# Degrees
+class TestDegreeView:
+    GRAPH = nx.Graph
+    dview = nx.reportviews.DegreeView
+
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(6, cls.GRAPH())
+        cls.G.add_edge(1, 3, foo=2)
+        cls.G.add_edge(1, 3, foo=3)
+
+    def test_pickle(self):
+        import pickle
+
+        deg = self.G.degree
+        pdeg = pickle.loads(pickle.dumps(deg, -1))
+        assert dict(deg) == dict(pdeg)
+
+    def test_str(self):
+        dv = self.dview(self.G)
+        rep = str([(0, 1), (1, 3), (2, 2), (3, 3), (4, 2), (5, 1)])
+        assert str(dv) == rep
+        dv = self.G.degree()
+        assert str(dv) == rep
+
+    def test_repr(self):
+        dv = self.dview(self.G)
+        rep = "DegreeView({0: 1, 1: 3, 2: 2, 3: 3, 4: 2, 5: 1})"
+        assert repr(dv) == rep
+
+    def test_iter(self):
+        dv = self.dview(self.G)
+        for n, d in dv:
+            pass
+        idv = iter(dv)
+        assert iter(dv) != dv
+        assert iter(idv) == idv
+        assert next(idv) == (0, dv[0])
+        assert next(idv) == (1, dv[1])
+        # weighted
+        dv = self.dview(self.G, weight="foo")
+        for n, d in dv:
+            pass
+        idv = iter(dv)
+        assert iter(dv) != dv
+        assert iter(idv) == idv
+        assert next(idv) == (0, dv[0])
+        assert next(idv) == (1, dv[1])
+
+    def test_nbunch(self):
+        dv = self.dview(self.G)
+        dvn = dv(0)
+        assert dvn == 1
+        dvn = dv([2, 3])
+        assert sorted(dvn) == [(2, 2), (3, 3)]
+
+    def test_getitem(self):
+        dv = self.dview(self.G)
+        assert dv[0] == 1
+        assert dv[1] == 3
+        assert dv[2] == 2
+        assert dv[3] == 3
+        dv = self.dview(self.G, weight="foo")
+        assert dv[0] == 1
+        assert dv[1] == 5
+        assert dv[2] == 2
+        assert dv[3] == 5
+
+    def test_weight(self):
+        dv = self.dview(self.G)
+        dvw = dv(0, weight="foo")
+        assert dvw == 1
+        dvw = dv(1, weight="foo")
+        assert dvw == 5
+        dvw = dv([2, 3], weight="foo")
+        assert sorted(dvw) == [(2, 2), (3, 5)]
+        dvd = dict(dv(weight="foo"))
+        assert dvd[0] == 1
+        assert dvd[1] == 5
+        assert dvd[2] == 2
+        assert dvd[3] == 5
+
+    def test_len(self):
+        dv = self.dview(self.G)
+        assert len(dv) == 6
+
+
+class TestDiDegreeView(TestDegreeView):
+    GRAPH = nx.DiGraph
+    dview = nx.reportviews.DiDegreeView
+
+    def test_repr(self):
+        dv = self.G.degree()
+        rep = "DiDegreeView({0: 1, 1: 3, 2: 2, 3: 3, 4: 2, 5: 1})"
+        assert repr(dv) == rep
+
+
+class TestOutDegreeView(TestDegreeView):
+    GRAPH = nx.DiGraph
+    dview = nx.reportviews.OutDegreeView
+
+    def test_str(self):
+        dv = self.dview(self.G)
+        rep = str([(0, 1), (1, 2), (2, 1), (3, 1), (4, 1), (5, 0)])
+        assert str(dv) == rep
+        dv = self.G.out_degree()
+        assert str(dv) == rep
+
+    def test_repr(self):
+        dv = self.G.out_degree()
+        rep = "OutDegreeView({0: 1, 1: 2, 2: 1, 3: 1, 4: 1, 5: 0})"
+        assert repr(dv) == rep
+
+    def test_nbunch(self):
+        dv = self.dview(self.G)
+        dvn = dv(0)
+        assert dvn == 1
+        dvn = dv([2, 3])
+        assert sorted(dvn) == [(2, 1), (3, 1)]
+
+    def test_getitem(self):
+        dv = self.dview(self.G)
+        assert dv[0] == 1
+        assert dv[1] == 2
+        assert dv[2] == 1
+        assert dv[3] == 1
+        dv = self.dview(self.G, weight="foo")
+        assert dv[0] == 1
+        assert dv[1] == 4
+        assert dv[2] == 1
+        assert dv[3] == 1
+
+    def test_weight(self):
+        dv = self.dview(self.G)
+        dvw = dv(0, weight="foo")
+        assert dvw == 1
+        dvw = dv(1, weight="foo")
+        assert dvw == 4
+        dvw = dv([2, 3], weight="foo")
+        assert sorted(dvw) == [(2, 1), (3, 1)]
+        dvd = dict(dv(weight="foo"))
+        assert dvd[0] == 1
+        assert dvd[1] == 4
+        assert dvd[2] == 1
+        assert dvd[3] == 1
+
+
+class TestInDegreeView(TestDegreeView):
+    GRAPH = nx.DiGraph
+    dview = nx.reportviews.InDegreeView
+
+    def test_str(self):
+        dv = self.dview(self.G)
+        rep = str([(0, 0), (1, 1), (2, 1), (3, 2), (4, 1), (5, 1)])
+        assert str(dv) == rep
+        dv = self.G.in_degree()
+        assert str(dv) == rep
+
+    def test_repr(self):
+        dv = self.G.in_degree()
+        rep = "InDegreeView({0: 0, 1: 1, 2: 1, 3: 2, 4: 1, 5: 1})"
+        assert repr(dv) == rep
+
+    def test_nbunch(self):
+        dv = self.dview(self.G)
+        dvn = dv(0)
+        assert dvn == 0
+        dvn = dv([2, 3])
+        assert sorted(dvn) == [(2, 1), (3, 2)]
+
+    def test_getitem(self):
+        dv = self.dview(self.G)
+        assert dv[0] == 0
+        assert dv[1] == 1
+        assert dv[2] == 1
+        assert dv[3] == 2
+        dv = self.dview(self.G, weight="foo")
+        assert dv[0] == 0
+        assert dv[1] == 1
+        assert dv[2] == 1
+        assert dv[3] == 4
+
+    def test_weight(self):
+        dv = self.dview(self.G)
+        dvw = dv(0, weight="foo")
+        assert dvw == 0
+        dvw = dv(1, weight="foo")
+        assert dvw == 1
+        dvw = dv([2, 3], weight="foo")
+        assert sorted(dvw) == [(2, 1), (3, 4)]
+        dvd = dict(dv(weight="foo"))
+        assert dvd[0] == 0
+        assert dvd[1] == 1
+        assert dvd[2] == 1
+        assert dvd[3] == 4
+
+
+class TestMultiDegreeView(TestDegreeView):
+    GRAPH = nx.MultiGraph
+    dview = nx.reportviews.MultiDegreeView
+
+    def test_str(self):
+        dv = self.dview(self.G)
+        rep = str([(0, 1), (1, 4), (2, 2), (3, 4), (4, 2), (5, 1)])
+        assert str(dv) == rep
+        dv = self.G.degree()
+        assert str(dv) == rep
+
+    def test_repr(self):
+        dv = self.G.degree()
+        rep = "MultiDegreeView({0: 1, 1: 4, 2: 2, 3: 4, 4: 2, 5: 1})"
+        assert repr(dv) == rep
+
+    def test_nbunch(self):
+        dv = self.dview(self.G)
+        dvn = dv(0)
+        assert dvn == 1
+        dvn = dv([2, 3])
+        assert sorted(dvn) == [(2, 2), (3, 4)]
+
+    def test_getitem(self):
+        dv = self.dview(self.G)
+        assert dv[0] == 1
+        assert dv[1] == 4
+        assert dv[2] == 2
+        assert dv[3] == 4
+        dv = self.dview(self.G, weight="foo")
+        assert dv[0] == 1
+        assert dv[1] == 7
+        assert dv[2] == 2
+        assert dv[3] == 7
+
+    def test_weight(self):
+        dv = self.dview(self.G)
+        dvw = dv(0, weight="foo")
+        assert dvw == 1
+        dvw = dv(1, weight="foo")
+        assert dvw == 7
+        dvw = dv([2, 3], weight="foo")
+        assert sorted(dvw) == [(2, 2), (3, 7)]
+        dvd = dict(dv(weight="foo"))
+        assert dvd[0] == 1
+        assert dvd[1] == 7
+        assert dvd[2] == 2
+        assert dvd[3] == 7
+
+
+class TestDiMultiDegreeView(TestMultiDegreeView):
+    GRAPH = nx.MultiDiGraph
+    dview = nx.reportviews.DiMultiDegreeView
+
+    def test_repr(self):
+        dv = self.G.degree()
+        rep = "DiMultiDegreeView({0: 1, 1: 4, 2: 2, 3: 4, 4: 2, 5: 1})"
+        assert repr(dv) == rep
+
+
+class TestOutMultiDegreeView(TestDegreeView):
+    GRAPH = nx.MultiDiGraph
+    dview = nx.reportviews.OutMultiDegreeView
+
+    def test_str(self):
+        dv = self.dview(self.G)
+        rep = str([(0, 1), (1, 3), (2, 1), (3, 1), (4, 1), (5, 0)])
+        assert str(dv) == rep
+        dv = self.G.out_degree()
+        assert str(dv) == rep
+
+    def test_repr(self):
+        dv = self.G.out_degree()
+        rep = "OutMultiDegreeView({0: 1, 1: 3, 2: 1, 3: 1, 4: 1, 5: 0})"
+        assert repr(dv) == rep
+
+    def test_nbunch(self):
+        dv = self.dview(self.G)
+        dvn = dv(0)
+        assert dvn == 1
+        dvn = dv([2, 3])
+        assert sorted(dvn) == [(2, 1), (3, 1)]
+
+    def test_getitem(self):
+        dv = self.dview(self.G)
+        assert dv[0] == 1
+        assert dv[1] == 3
+        assert dv[2] == 1
+        assert dv[3] == 1
+        dv = self.dview(self.G, weight="foo")
+        assert dv[0] == 1
+        assert dv[1] == 6
+        assert dv[2] == 1
+        assert dv[3] == 1
+
+    def test_weight(self):
+        dv = self.dview(self.G)
+        dvw = dv(0, weight="foo")
+        assert dvw == 1
+        dvw = dv(1, weight="foo")
+        assert dvw == 6
+        dvw = dv([2, 3], weight="foo")
+        assert sorted(dvw) == [(2, 1), (3, 1)]
+        dvd = dict(dv(weight="foo"))
+        assert dvd[0] == 1
+        assert dvd[1] == 6
+        assert dvd[2] == 1
+        assert dvd[3] == 1
+
+
+class TestInMultiDegreeView(TestDegreeView):
+    GRAPH = nx.MultiDiGraph
+    dview = nx.reportviews.InMultiDegreeView
+
+    def test_str(self):
+        dv = self.dview(self.G)
+        rep = str([(0, 0), (1, 1), (2, 1), (3, 3), (4, 1), (5, 1)])
+        assert str(dv) == rep
+        dv = self.G.in_degree()
+        assert str(dv) == rep
+
+    def test_repr(self):
+        dv = self.G.in_degree()
+        rep = "InMultiDegreeView({0: 0, 1: 1, 2: 1, 3: 3, 4: 1, 5: 1})"
+        assert repr(dv) == rep
+
+    def test_nbunch(self):
+        dv = self.dview(self.G)
+        dvn = dv(0)
+        assert dvn == 0
+        dvn = dv([2, 3])
+        assert sorted(dvn) == [(2, 1), (3, 3)]
+
+    def test_getitem(self):
+        dv = self.dview(self.G)
+        assert dv[0] == 0
+        assert dv[1] == 1
+        assert dv[2] == 1
+        assert dv[3] == 3
+        dv = self.dview(self.G, weight="foo")
+        assert dv[0] == 0
+        assert dv[1] == 1
+        assert dv[2] == 1
+        assert dv[3] == 6
+
+    def test_weight(self):
+        dv = self.dview(self.G)
+        dvw = dv(0, weight="foo")
+        assert dvw == 0
+        dvw = dv(1, weight="foo")
+        assert dvw == 1
+        dvw = dv([2, 3], weight="foo")
+        assert sorted(dvw) == [(2, 1), (3, 6)]
+        dvd = dict(dv(weight="foo"))
+        assert dvd[0] == 0
+        assert dvd[1] == 1
+        assert dvd[2] == 1
+        assert dvd[3] == 6
+
+
+@pytest.mark.parametrize(
+    ("reportview", "err_msg_terms"),
+    (
+        (rv.NodeView, "list(G.nodes"),
+        (rv.NodeDataView, "list(G.nodes.data"),
+        (rv.EdgeView, "list(G.edges"),
+        # Directed EdgeViews
+        (rv.InEdgeView, "list(G.in_edges"),
+        (rv.OutEdgeView, "list(G.edges"),
+        # Multi EdgeViews
+        (rv.MultiEdgeView, "list(G.edges"),
+        (rv.InMultiEdgeView, "list(G.in_edges"),
+        (rv.OutMultiEdgeView, "list(G.edges"),
+    ),
+)
+def test_slicing_reportviews(reportview, err_msg_terms):
+    G = nx.complete_graph(3)
+    view = reportview(G)
+    with pytest.raises(nx.NetworkXError) as exc:
+        view[0:2]
+    errmsg = str(exc.value)
+    assert type(view).__name__ in errmsg
+    assert err_msg_terms in errmsg
+
+
+@pytest.mark.parametrize(
+    "graph", [nx.Graph, nx.DiGraph, nx.MultiGraph, nx.MultiDiGraph]
+)
+def test_cache_dict_get_set_state(graph):
+    G = nx.path_graph(5, graph())
+    G.nodes, G.edges, G.adj, G.degree
+    if G.is_directed():
+        G.pred, G.succ, G.in_edges, G.out_edges, G.in_degree, G.out_degree
+    cached_dict = G.__dict__
+    assert "nodes" in cached_dict
+    assert "edges" in cached_dict
+    assert "adj" in cached_dict
+    assert "degree" in cached_dict
+    if G.is_directed():
+        assert "pred" in cached_dict
+        assert "succ" in cached_dict
+        assert "in_edges" in cached_dict
+        assert "out_edges" in cached_dict
+        assert "in_degree" in cached_dict
+        assert "out_degree" in cached_dict
+
+    # Raises error if the cached properties and views do not work
+    pickle.loads(pickle.dumps(G, -1))
+    deepcopy(G)

venv/lib/python3.10/site-packages/networkx/classes/tests/test_special.py

@@ -0,0 +1,131 @@
+import networkx as nx
+
+from .test_digraph import BaseDiGraphTester
+from .test_digraph import TestDiGraph as _TestDiGraph
+from .test_graph import BaseGraphTester
+from .test_graph import TestGraph as _TestGraph
+from .test_multidigraph import TestMultiDiGraph as _TestMultiDiGraph
+from .test_multigraph import TestMultiGraph as _TestMultiGraph
+
+
+def test_factories():
+    class mydict1(dict):
+        pass
+
+    class mydict2(dict):
+        pass
+
+    class mydict3(dict):
+        pass
+
+    class mydict4(dict):
+        pass
+
+    class mydict5(dict):
+        pass
+
+    for Graph in (nx.Graph, nx.DiGraph, nx.MultiGraph, nx.MultiDiGraph):
+        # print("testing class: ", Graph.__name__)
+        class MyGraph(Graph):
+            node_dict_factory = mydict1
+            adjlist_outer_dict_factory = mydict2
+            adjlist_inner_dict_factory = mydict3
+            edge_key_dict_factory = mydict4
+            edge_attr_dict_factory = mydict5
+
+        G = MyGraph()
+        assert isinstance(G._node, mydict1)
+        assert isinstance(G._adj, mydict2)
+        G.add_node(1)
+        assert isinstance(G._adj[1], mydict3)
+        if G.is_directed():
+            assert isinstance(G._pred, mydict2)
+            assert isinstance(G._succ, mydict2)
+            assert isinstance(G._pred[1], mydict3)
+        G.add_edge(1, 2)
+        if G.is_multigraph():
+            assert isinstance(G._adj[1][2], mydict4)
+            assert isinstance(G._adj[1][2][0], mydict5)
+        else:
+            assert isinstance(G._adj[1][2], mydict5)
+
+
+class TestSpecialGraph(_TestGraph):
+    def setup_method(self):
+        _TestGraph.setup_method(self)
+        self.Graph = nx.Graph
+
+
+class TestThinGraph(BaseGraphTester):
+    def setup_method(self):
+        all_edge_dict = {"weight": 1}
+
+        class MyGraph(nx.Graph):
+            def edge_attr_dict_factory(self):
+                return all_edge_dict
+
+        self.Graph = MyGraph
+        # build dict-of-dict-of-dict K3
+        ed1, ed2, ed3 = (all_edge_dict, all_edge_dict, all_edge_dict)
+        self.k3adj = {0: {1: ed1, 2: ed2}, 1: {0: ed1, 2: ed3}, 2: {0: ed2, 1: ed3}}
+        self.k3edges = [(0, 1), (0, 2), (1, 2)]
+        self.k3nodes = [0, 1, 2]
+        self.K3 = self.Graph()
+        self.K3._adj = self.k3adj
+        self.K3._node = {}
+        self.K3._node[0] = {}
+        self.K3._node[1] = {}
+        self.K3._node[2] = {}
+
+
+class TestSpecialDiGraph(_TestDiGraph):
+    def setup_method(self):
+        _TestDiGraph.setup_method(self)
+        self.Graph = nx.DiGraph
+
+
+class TestThinDiGraph(BaseDiGraphTester):
+    def setup_method(self):
+        all_edge_dict = {"weight": 1}
+
+        class MyGraph(nx.DiGraph):
+            def edge_attr_dict_factory(self):
+                return all_edge_dict
+
+        self.Graph = MyGraph
+        # build dict-of-dict-of-dict K3
+        ed1, ed2, ed3 = (all_edge_dict, all_edge_dict, all_edge_dict)
+        ed4, ed5, ed6 = (all_edge_dict, all_edge_dict, all_edge_dict)
+        self.k3adj = {0: {1: ed1, 2: ed2}, 1: {0: ed3, 2: ed4}, 2: {0: ed5, 1: ed6}}
+        self.k3edges = [(0, 1), (0, 2), (1, 2)]
+        self.k3nodes = [0, 1, 2]
+        self.K3 = self.Graph()
+        self.K3._succ = self.k3adj
+        # K3._adj is synced with K3._succ
+        self.K3._pred = {0: {1: ed3, 2: ed5}, 1: {0: ed1, 2: ed6}, 2: {0: ed2, 1: ed4}}
+        self.K3._node = {}
+        self.K3._node[0] = {}
+        self.K3._node[1] = {}
+        self.K3._node[2] = {}
+
+        ed1, ed2 = (all_edge_dict, all_edge_dict)
+        self.P3 = self.Graph()
+        self.P3._succ = {0: {1: ed1}, 1: {2: ed2}, 2: {}}
+        # P3._adj is synced with P3._succ
+        self.P3._pred = {0: {}, 1: {0: ed1}, 2: {1: ed2}}
+        self.P3._node = {}
+        self.P3._node[0] = {}
+        self.P3._node[1] = {}
+        self.P3._node[2] = {}
+
+
+class TestSpecialMultiGraph(_TestMultiGraph):
+    def setup_method(self):
+        _TestMultiGraph.setup_method(self)
+        self.Graph = nx.MultiGraph
+
+
+class TestSpecialMultiDiGraph(_TestMultiDiGraph):
+    def setup_method(self):
+        _TestMultiDiGraph.setup_method(self)
+        self.Graph = nx.MultiDiGraph

venv/lib/python3.10/site-packages/networkx/classes/tests/test_subgraphviews.py

@@ -0,0 +1,362 @@
+import pytest
+
+import networkx as nx
+from networkx.utils import edges_equal
+
+
+class TestSubGraphView:
+    gview = staticmethod(nx.subgraph_view)
+    graph = nx.Graph
+    hide_edges_filter = staticmethod(nx.filters.hide_edges)
+    show_edges_filter = staticmethod(nx.filters.show_edges)
+
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9, create_using=cls.graph())
+        cls.hide_edges_w_hide_nodes = {(3, 4), (4, 5), (5, 6)}
+
+    def test_hidden_nodes(self):
+        hide_nodes = [4, 5, 111]
+        nodes_gone = nx.filters.hide_nodes(hide_nodes)
+        gview = self.gview
+        G = gview(self.G, filter_node=nodes_gone)
+        assert self.G.nodes - G.nodes == {4, 5}
+        assert self.G.edges - G.edges == self.hide_edges_w_hide_nodes
+        if G.is_directed():
+            assert list(G[3]) == []
+            assert list(G[2]) == [3]
+        else:
+            assert list(G[3]) == [2]
+            assert set(G[2]) == {1, 3}
+        pytest.raises(KeyError, G.__getitem__, 4)
+        pytest.raises(KeyError, G.__getitem__, 112)
+        pytest.raises(KeyError, G.__getitem__, 111)
+        assert G.degree(3) == (3 if G.is_multigraph() else 1)
+        assert G.size() == (7 if G.is_multigraph() else 5)
+
+    def test_hidden_edges(self):
+        hide_edges = [(2, 3), (8, 7), (222, 223)]
+        edges_gone = self.hide_edges_filter(hide_edges)
+        gview = self.gview
+        G = gview(self.G, filter_edge=edges_gone)
+        assert self.G.nodes == G.nodes
+        if G.is_directed():
+            assert self.G.edges - G.edges == {(2, 3)}
+            assert list(G[2]) == []
+            assert list(G.pred[3]) == []
+            assert list(G.pred[2]) == [1]
+            assert G.size() == 7
+        else:
+            assert self.G.edges - G.edges == {(2, 3), (7, 8)}
+            assert list(G[2]) == [1]
+            assert G.size() == 6
+        assert list(G[3]) == [4]
+        pytest.raises(KeyError, G.__getitem__, 221)
+        pytest.raises(KeyError, G.__getitem__, 222)
+        assert G.degree(3) == 1
+
+    def test_shown_node(self):
+        induced_subgraph = nx.filters.show_nodes([2, 3, 111])
+        gview = self.gview
+        G = gview(self.G, filter_node=induced_subgraph)
+        assert set(G.nodes) == {2, 3}
+        if G.is_directed():
+            assert list(G[3]) == []
+        else:
+            assert list(G[3]) == [2]
+        assert list(G[2]) == [3]
+        pytest.raises(KeyError, G.__getitem__, 4)
+        pytest.raises(KeyError, G.__getitem__, 112)
+        pytest.raises(KeyError, G.__getitem__, 111)
+        assert G.degree(3) == (3 if G.is_multigraph() else 1)
+        assert G.size() == (3 if G.is_multigraph() else 1)
+
+    def test_shown_edges(self):
+        show_edges = [(2, 3), (8, 7), (222, 223)]
+        edge_subgraph = self.show_edges_filter(show_edges)
+        G = self.gview(self.G, filter_edge=edge_subgraph)
+        assert self.G.nodes == G.nodes
+        if G.is_directed():
+            assert G.edges == {(2, 3)}
+            assert list(G[3]) == []
+            assert list(G[2]) == [3]
+            assert list(G.pred[3]) == [2]
+            assert list(G.pred[2]) == []
+            assert G.size() == 1
+        else:
+            assert G.edges == {(2, 3), (7, 8)}
+            assert list(G[3]) == [2]
+            assert list(G[2]) == [3]
+            assert G.size() == 2
+        pytest.raises(KeyError, G.__getitem__, 221)
+        pytest.raises(KeyError, G.__getitem__, 222)
+        assert G.degree(3) == 1
+
+
+class TestSubDiGraphView(TestSubGraphView):
+    gview = staticmethod(nx.subgraph_view)
+    graph = nx.DiGraph
+    hide_edges_filter = staticmethod(nx.filters.hide_diedges)
+    show_edges_filter = staticmethod(nx.filters.show_diedges)
+    hide_edges = [(2, 3), (8, 7), (222, 223)]
+    excluded = {(2, 3), (3, 4), (4, 5), (5, 6)}
+
+    def test_inoutedges(self):
+        edges_gone = self.hide_edges_filter(self.hide_edges)
+        hide_nodes = [4, 5, 111]
+        nodes_gone = nx.filters.hide_nodes(hide_nodes)
+        G = self.gview(self.G, filter_node=nodes_gone, filter_edge=edges_gone)
+
+        assert self.G.in_edges - G.in_edges == self.excluded
+        assert self.G.out_edges - G.out_edges == self.excluded
+
+    def test_pred(self):
+        edges_gone = self.hide_edges_filter(self.hide_edges)
+        hide_nodes = [4, 5, 111]
+        nodes_gone = nx.filters.hide_nodes(hide_nodes)
+        G = self.gview(self.G, filter_node=nodes_gone, filter_edge=edges_gone)
+
+        assert list(G.pred[2]) == [1]
+        assert list(G.pred[6]) == []
+
+    def test_inout_degree(self):
+        edges_gone = self.hide_edges_filter(self.hide_edges)
+        hide_nodes = [4, 5, 111]
+        nodes_gone = nx.filters.hide_nodes(hide_nodes)
+        G = self.gview(self.G, filter_node=nodes_gone, filter_edge=edges_gone)
+
+        assert G.degree(2) == 1
+        assert G.out_degree(2) == 0
+        assert G.in_degree(2) == 1
+        assert G.size() == 4
+
+
+# multigraph
+class TestMultiGraphView(TestSubGraphView):
+    gview = staticmethod(nx.subgraph_view)
+    graph = nx.MultiGraph
+    hide_edges_filter = staticmethod(nx.filters.hide_multiedges)
+    show_edges_filter = staticmethod(nx.filters.show_multiedges)
+
+    @classmethod
+    def setup_class(cls):
+        cls.G = nx.path_graph(9, create_using=cls.graph())
+        multiedges = {(2, 3, 4), (2, 3, 5)}
+        cls.G.add_edges_from(multiedges)
+        cls.hide_edges_w_hide_nodes = {(3, 4, 0), (4, 5, 0), (5, 6, 0)}
+
+    def test_hidden_edges(self):
+        hide_edges = [(2, 3, 4), (2, 3, 3), (8, 7, 0), (222, 223, 0)]
+        edges_gone = self.hide_edges_filter(hide_edges)
+        G = self.gview(self.G, filter_edge=edges_gone)
+        assert self.G.nodes == G.nodes
+        if G.is_directed():
+            assert self.G.edges - G.edges == {(2, 3, 4)}
+            assert list(G[3]) == [4]
+            assert list(G[2]) == [3]
+            assert list(G.pred[3]) == [2]  # only one 2 but two edges
+            assert list(G.pred[2]) == [1]
+            assert G.size() == 9
+        else:
+            assert self.G.edges - G.edges == {(2, 3, 4), (7, 8, 0)}
+            assert list(G[3]) == [2, 4]
+            assert list(G[2]) == [1, 3]
+            assert G.size() == 8
+        assert G.degree(3) == 3
+        pytest.raises(KeyError, G.__getitem__, 221)
+        pytest.raises(KeyError, G.__getitem__, 222)
+
+    def test_shown_edges(self):
+        show_edges = [(2, 3, 4), (2, 3, 3), (8, 7, 0), (222, 223, 0)]
+        edge_subgraph = self.show_edges_filter(show_edges)
+        G = self.gview(self.G, filter_edge=edge_subgraph)
+        assert self.G.nodes == G.nodes
+        if G.is_directed():
+            assert G.edges == {(2, 3, 4)}
+            assert list(G[3]) == []
+            assert list(G.pred[3]) == [2]
+            assert list(G.pred[2]) == []
+            assert G.size() == 1
+        else:
+            assert G.edges == {(2, 3, 4), (7, 8, 0)}
+            assert G.size() == 2
+            assert list(G[3]) == [2]
+        assert G.degree(3) == 1
+        assert list(G[2]) == [3]
+        pytest.raises(KeyError, G.__getitem__, 221)
+        pytest.raises(KeyError, G.__getitem__, 222)
+
+
+# multidigraph
+class TestMultiDiGraphView(TestMultiGraphView, TestSubDiGraphView):
+    gview = staticmethod(nx.subgraph_view)
+    graph = nx.MultiDiGraph
+    hide_edges_filter = staticmethod(nx.filters.hide_multidiedges)
+    show_edges_filter = staticmethod(nx.filters.show_multidiedges)
+    hide_edges = [(2, 3, 0), (8, 7, 0), (222, 223, 0)]
+    excluded = {(2, 3, 0), (3, 4, 0), (4, 5, 0), (5, 6, 0)}
+
+    def test_inout_degree(self):
+        edges_gone = self.hide_edges_filter(self.hide_edges)
+        hide_nodes = [4, 5, 111]
+        nodes_gone = nx.filters.hide_nodes(hide_nodes)
+        G = self.gview(self.G, filter_node=nodes_gone, filter_edge=edges_gone)
+
+        assert G.degree(2) == 3
+        assert G.out_degree(2) == 2
+        assert G.in_degree(2) == 1
+        assert G.size() == 6
+
+
+# induced_subgraph
+class TestInducedSubGraph:
+    @classmethod
+    def setup_class(cls):
+        cls.K3 = G = nx.complete_graph(3)
+        G.graph["foo"] = []
+        G.nodes[0]["foo"] = []
+        G.remove_edge(1, 2)
+        ll = []
+        G.add_edge(1, 2, foo=ll)
+        G.add_edge(2, 1, foo=ll)
+
+    def test_full_graph(self):
+        G = self.K3
+        H = nx.induced_subgraph(G, [0, 1, 2, 5])
+        assert H.name == G.name
+        self.graphs_equal(H, G)
+        self.same_attrdict(H, G)
+
+    def test_partial_subgraph(self):
+        G = self.K3
+        H = nx.induced_subgraph(G, 0)
+        assert dict(H.adj) == {0: {}}
+        assert dict(G.adj) != {0: {}}
+
+        H = nx.induced_subgraph(G, [0, 1])
+        assert dict(H.adj) == {0: {1: {}}, 1: {0: {}}}
+
+    def same_attrdict(self, H, G):
+        old_foo = H[1][2]["foo"]
+        H.edges[1, 2]["foo"] = "baz"
+        assert G.edges == H.edges
+        H.edges[1, 2]["foo"] = old_foo
+        assert G.edges == H.edges
+        old_foo = H.nodes[0]["foo"]
+        H.nodes[0]["foo"] = "baz"
+        assert G.nodes == H.nodes
+        H.nodes[0]["foo"] = old_foo
+        assert G.nodes == H.nodes
+
+    def graphs_equal(self, H, G):
+        assert G._adj == H._adj
+        assert G._node == H._node
+        assert G.graph == H.graph
+        assert G.name == H.name
+        if not G.is_directed() and not H.is_directed():
+            assert H._adj[1][2] is H._adj[2][1]
+            assert G._adj[1][2] is G._adj[2][1]
+        else:  # at least one is directed
+            if not G.is_directed():
+                G._pred = G._adj
+                G._succ = G._adj
+            if not H.is_directed():
+                H._pred = H._adj
+                H._succ = H._adj
+            assert G._pred == H._pred
+            assert G._succ == H._succ
+            assert H._succ[1][2] is H._pred[2][1]
+            assert G._succ[1][2] is G._pred[2][1]
+
+
+# edge_subgraph
+class TestEdgeSubGraph:
+    @classmethod
+    def setup_class(cls):
+        # Create a path graph on five nodes.
+        cls.G = G = nx.path_graph(5)
+        # Add some node, edge, and graph attributes.
+        for i in range(5):
+            G.nodes[i]["name"] = f"node{i}"
+        G.edges[0, 1]["name"] = "edge01"
+        G.edges[3, 4]["name"] = "edge34"
+        G.graph["name"] = "graph"
+        # Get the subgraph induced by the first and last edges.
+        cls.H = nx.edge_subgraph(G, [(0, 1), (3, 4)])
+
+    def test_correct_nodes(self):
+        """Tests that the subgraph has the correct nodes."""
+        assert [(0, "node0"), (1, "node1"), (3, "node3"), (4, "node4")] == sorted(
+            self.H.nodes.data("name")
+        )
+
+    def test_correct_edges(self):
+        """Tests that the subgraph has the correct edges."""
+        assert edges_equal(
+            [(0, 1, "edge01"), (3, 4, "edge34")], self.H.edges.data("name")
+        )
+
+    def test_add_node(self):
+        """Tests that adding a node to the original graph does not
+        affect the nodes of the subgraph.
+
+        """
+        self.G.add_node(5)
+        assert [0, 1, 3, 4] == sorted(self.H.nodes)
+        self.G.remove_node(5)
+
+    def test_remove_node(self):
+        """Tests that removing a node in the original graph
+        removes the nodes of the subgraph.
+
+        """
+        self.G.remove_node(0)
+        assert [1, 3, 4] == sorted(self.H.nodes)
+        self.G.add_node(0, name="node0")
+        self.G.add_edge(0, 1, name="edge01")
+
+    def test_node_attr_dict(self):
+        """Tests that the node attribute dictionary of the two graphs is
+        the same object.
+
+        """
+        for v in self.H:
+            assert self.G.nodes[v] == self.H.nodes[v]
+        # Making a change to G should make a change in H and vice versa.
+        self.G.nodes[0]["name"] = "foo"
+        assert self.G.nodes[0] == self.H.nodes[0]
+        self.H.nodes[1]["name"] = "bar"
+        assert self.G.nodes[1] == self.H.nodes[1]
+        # Revert the change, so tests pass with pytest-randomly
+        self.G.nodes[0]["name"] = "node0"
+        self.H.nodes[1]["name"] = "node1"
+
+    def test_edge_attr_dict(self):
+        """Tests that the edge attribute dictionary of the two graphs is
+        the same object.
+
+        """
+        for u, v in self.H.edges():
+            assert self.G.edges[u, v] == self.H.edges[u, v]
+        # Making a change to G should make a change in H and vice versa.
+        self.G.edges[0, 1]["name"] = "foo"
+        assert self.G.edges[0, 1]["name"] == self.H.edges[0, 1]["name"]
+        self.H.edges[3, 4]["name"] = "bar"
+        assert self.G.edges[3, 4]["name"] == self.H.edges[3, 4]["name"]
+        # Revert the change, so tests pass with pytest-randomly
+        self.G.edges[0, 1]["name"] = "edge01"
+        self.H.edges[3, 4]["name"] = "edge34"
+
+    def test_graph_attr_dict(self):
+        """Tests that the graph attribute dictionary of the two graphs
+        is the same object.
+
+        """
+        assert self.G.graph is self.H.graph
+
+    def test_readonly(self):
+        """Tests that the subgraph cannot change the graph structure"""
+        pytest.raises(nx.NetworkXError, self.H.add_node, 5)
+        pytest.raises(nx.NetworkXError, self.H.remove_node, 0)
+        pytest.raises(nx.NetworkXError, self.H.add_edge, 5, 6)
+        pytest.raises(nx.NetworkXError, self.H.remove_edge, 0, 1)

venv/lib/python3.10/site-packages/urllib3/__init__.py

@@ -0,0 +1,211 @@
+"""
+Python HTTP library with thread-safe connection pooling, file post support, user friendly, and more
+"""
+
+from __future__ import annotations
+
+# Set default logging handler to avoid "No handler found" warnings.
+import logging
+import sys
+import typing
+import warnings
+from logging import NullHandler
+
+from . import exceptions
+from ._base_connection import _TYPE_BODY
+from ._collections import HTTPHeaderDict
+from ._version import __version__
+from .connectionpool import HTTPConnectionPool, HTTPSConnectionPool, connection_from_url
+from .filepost import _TYPE_FIELDS, encode_multipart_formdata
+from .poolmanager import PoolManager, ProxyManager, proxy_from_url
+from .response import BaseHTTPResponse, HTTPResponse
+from .util.request import make_headers
+from .util.retry import Retry
+from .util.timeout import Timeout
+
+# Ensure that Python is compiled with OpenSSL 1.1.1+
+# If the 'ssl' module isn't available at all that's
+# fine, we only care if the module is available.
+try:
+    import ssl
+except ImportError:
+    pass
+else:
+    if not ssl.OPENSSL_VERSION.startswith("OpenSSL "):  # Defensive:
+        warnings.warn(
+            "urllib3 v2 only supports OpenSSL 1.1.1+, currently "
+            f"the 'ssl' module is compiled with {ssl.OPENSSL_VERSION!r}. "
+            "See: https://github.com/urllib3/urllib3/issues/3020",
+            exceptions.NotOpenSSLWarning,
+        )
+    elif ssl.OPENSSL_VERSION_INFO < (1, 1, 1):  # Defensive:
+        raise ImportError(
+            "urllib3 v2 only supports OpenSSL 1.1.1+, currently "
+            f"the 'ssl' module is compiled with {ssl.OPENSSL_VERSION!r}. "
+            "See: https://github.com/urllib3/urllib3/issues/2168"
+        )
+
+__author__ = "Andrey Petrov ([email protected])"
+__license__ = "MIT"
+__version__ = __version__
+
+__all__ = (
+    "HTTPConnectionPool",
+    "HTTPHeaderDict",
+    "HTTPSConnectionPool",
+    "PoolManager",
+    "ProxyManager",
+    "HTTPResponse",
+    "Retry",
+    "Timeout",
+    "add_stderr_logger",
+    "connection_from_url",
+    "disable_warnings",
+    "encode_multipart_formdata",
+    "make_headers",
+    "proxy_from_url",
+    "request",
+    "BaseHTTPResponse",
+)
+
+logging.getLogger(__name__).addHandler(NullHandler())
+
+
+def add_stderr_logger(
+    level: int = logging.DEBUG,
+) -> logging.StreamHandler[typing.TextIO]:
+    """
+    Helper for quickly adding a StreamHandler to the logger. Useful for
+    debugging.
+
+    Returns the handler after adding it.
+    """
+    # This method needs to be in this __init__.py to get the __name__ correct
+    # even if urllib3 is vendored within another package.
+    logger = logging.getLogger(__name__)
+    handler = logging.StreamHandler()
+    handler.setFormatter(logging.Formatter("%(asctime)s %(levelname)s %(message)s"))
+    logger.addHandler(handler)
+    logger.setLevel(level)
+    logger.debug("Added a stderr logging handler to logger: %s", __name__)
+    return handler
+
+
+# ... Clean up.
+del NullHandler
+
+
+# All warning filters *must* be appended unless you're really certain that they
+# shouldn't be: otherwise, it's very hard for users to use most Python
+# mechanisms to silence them.
+# SecurityWarning's always go off by default.
+warnings.simplefilter("always", exceptions.SecurityWarning, append=True)
+# InsecurePlatformWarning's don't vary between requests, so we keep it default.
+warnings.simplefilter("default", exceptions.InsecurePlatformWarning, append=True)
+
+
+def disable_warnings(category: type[Warning] = exceptions.HTTPWarning) -> None:
+    """
+    Helper for quickly disabling all urllib3 warnings.
+    """
+    warnings.simplefilter("ignore", category)
+
+
+_DEFAULT_POOL = PoolManager()
+
+
+def request(
+    method: str,
+    url: str,
+    *,
+    body: _TYPE_BODY | None = None,
+    fields: _TYPE_FIELDS | None = None,
+    headers: typing.Mapping[str, str] | None = None,
+    preload_content: bool | None = True,
+    decode_content: bool | None = True,
+    redirect: bool | None = True,
+    retries: Retry | bool | int | None = None,
+    timeout: Timeout | float | int | None = 3,
+    json: typing.Any | None = None,
+) -> BaseHTTPResponse:
+    """
+    A convenience, top-level request method. It uses a module-global ``PoolManager`` instance.
+    Therefore, its side effects could be shared across dependencies relying on it.
+    To avoid side effects create a new ``PoolManager`` instance and use it instead.
+    The method does not accept low-level ``**urlopen_kw`` keyword arguments.
+
+    :param method:
+        HTTP request method (such as GET, POST, PUT, etc.)
+
+    :param url:
+        The URL to perform the request on.
+
+    :param body:
+        Data to send in the request body, either :class:`str`, :class:`bytes`,
+        an iterable of :class:`str`/:class:`bytes`, or a file-like object.
+
+    :param fields:
+        Data to encode and send in the request body.
+
+    :param headers:
+        Dictionary of custom headers to send, such as User-Agent,
+        If-None-Match, etc.
+
+    :param bool preload_content:
+        If True, the response's body will be preloaded into memory.
+
+    :param bool decode_content:
+        If True, will attempt to decode the body based on the
+        'content-encoding' header.
+
+    :param redirect:
+        If True, automatically handle redirects (status codes 301, 302,
+        303, 307, 308). Each redirect counts as a retry. Disabling retries
+        will disable redirect, too.
+
+    :param retries:
+        Configure the number of retries to allow before raising a
+        :class:`~urllib3.exceptions.MaxRetryError` exception.
+
+        If ``None`` (default) will retry 3 times, see ``Retry.DEFAULT``. Pass a
+        :class:`~urllib3.util.retry.Retry` object for fine-grained control
+        over different types of retries.
+        Pass an integer number to retry connection errors that many times,
+        but no other types of errors. Pass zero to never retry.
+
+        If ``False``, then retries are disabled and any exception is raised
+        immediately. Also, instead of raising a MaxRetryError on redirects,
+        the redirect response will be returned.
+
+    :type retries: :class:`~urllib3.util.retry.Retry`, False, or an int.
+
+    :param timeout:
+        If specified, overrides the default timeout for this one
+        request. It may be a float (in seconds) or an instance of
+        :class:`urllib3.util.Timeout`.
+
+    :param json:
+        Data to encode and send as JSON with UTF-encoded in the request body.
+        The ``"Content-Type"`` header will be set to ``"application/json"``
+        unless specified otherwise.
+    """
+
+    return _DEFAULT_POOL.request(
+        method,
+        url,
+        body=body,
+        fields=fields,
+        headers=headers,
+        preload_content=preload_content,
+        decode_content=decode_content,
+        redirect=redirect,
+        retries=retries,
+        timeout=timeout,
+        json=json,
+    )
+
+
+if sys.platform == "emscripten":
+    from .contrib.emscripten import inject_into_urllib3  # noqa: 401
+
+    inject_into_urllib3()

venv/lib/python3.10/site-packages/urllib3/_base_connection.py

@@ -0,0 +1,172 @@
+from __future__ import annotations
+
+import typing
+
+from .util.connection import _TYPE_SOCKET_OPTIONS
+from .util.timeout import _DEFAULT_TIMEOUT, _TYPE_TIMEOUT
+from .util.url import Url
+
+_TYPE_BODY = typing.Union[bytes, typing.IO[typing.Any], typing.Iterable[bytes], str]
+
+
+class ProxyConfig(typing.NamedTuple):
+    ssl_context: ssl.SSLContext | None
+    use_forwarding_for_https: bool
+    assert_hostname: None | str | Literal[False]
+    assert_fingerprint: str | None
+
+
+class _ResponseOptions(typing.NamedTuple):
+    # TODO: Remove this in favor of a better
+    # HTTP request/response lifecycle tracking.
+    request_method: str
+    request_url: str
+    preload_content: bool
+    decode_content: bool
+    enforce_content_length: bool
+
+
+if typing.TYPE_CHECKING:
+    import ssl
+    from typing import Literal, Protocol
+
+    from .response import BaseHTTPResponse
+
+    class BaseHTTPConnection(Protocol):
+        default_port: typing.ClassVar[int]
+        default_socket_options: typing.ClassVar[_TYPE_SOCKET_OPTIONS]
+
+        host: str
+        port: int
+        timeout: None | (
+            float
+        )  # Instance doesn't store _DEFAULT_TIMEOUT, must be resolved.
+        blocksize: int
+        source_address: tuple[str, int] | None
+        socket_options: _TYPE_SOCKET_OPTIONS | None
+
+        proxy: Url | None
+        proxy_config: ProxyConfig | None
+
+        is_verified: bool
+        proxy_is_verified: bool | None
+
+        def __init__(
+            self,
+            host: str,
+            port: int | None = None,
+            *,
+            timeout: _TYPE_TIMEOUT = _DEFAULT_TIMEOUT,
+            source_address: tuple[str, int] | None = None,
+            blocksize: int = 8192,
+            socket_options: _TYPE_SOCKET_OPTIONS | None = ...,
+            proxy: Url | None = None,
+            proxy_config: ProxyConfig | None = None,
+        ) -> None:
+            ...
+
+        def set_tunnel(
+            self,
+            host: str,
+            port: int | None = None,
+            headers: typing.Mapping[str, str] | None = None,
+            scheme: str = "http",
+        ) -> None:
+            ...
+
+        def connect(self) -> None:
+            ...
+
+        def request(
+            self,
+            method: str,
+            url: str,
+            body: _TYPE_BODY | None = None,
+            headers: typing.Mapping[str, str] | None = None,
+            # We know *at least* botocore is depending on the order of the
+            # first 3 parameters so to be safe we only mark the later ones
+            # as keyword-only to ensure we have space to extend.
+            *,
+            chunked: bool = False,
+            preload_content: bool = True,
+            decode_content: bool = True,
+            enforce_content_length: bool = True,
+        ) -> None:
+            ...
+
+        def getresponse(self) -> BaseHTTPResponse:
+            ...
+
+        def close(self) -> None:
+            ...
+
+        @property
+        def is_closed(self) -> bool:
+            """Whether the connection either is brand new or has been previously closed.
+            If this property is True then both ``is_connected`` and ``has_connected_to_proxy``
+            properties must be False.
+            """
+
+        @property
+        def is_connected(self) -> bool:
+            """Whether the connection is actively connected to any origin (proxy or target)"""
+
+        @property
+        def has_connected_to_proxy(self) -> bool:
+            """Whether the connection has successfully connected to its proxy.
+            This returns False if no proxy is in use. Used to determine whether
+            errors are coming from the proxy layer or from tunnelling to the target origin.
+            """
+
+    class BaseHTTPSConnection(BaseHTTPConnection, Protocol):
+        default_port: typing.ClassVar[int]
+        default_socket_options: typing.ClassVar[_TYPE_SOCKET_OPTIONS]
+
+        # Certificate verification methods
+        cert_reqs: int | str | None
+        assert_hostname: None | str | Literal[False]
+        assert_fingerprint: str | None
+        ssl_context: ssl.SSLContext | None
+
+        # Trusted CAs
+        ca_certs: str | None
+        ca_cert_dir: str | None
+        ca_cert_data: None | str | bytes
+
+        # TLS version
+        ssl_minimum_version: int | None
+        ssl_maximum_version: int | None
+        ssl_version: int | str | None  # Deprecated
+
+        # Client certificates
+        cert_file: str | None
+        key_file: str | None
+        key_password: str | None
+
+        def __init__(
+            self,
+            host: str,
+            port: int | None = None,
+            *,
+            timeout: _TYPE_TIMEOUT = _DEFAULT_TIMEOUT,
+            source_address: tuple[str, int] | None = None,
+            blocksize: int = 16384,
+            socket_options: _TYPE_SOCKET_OPTIONS | None = ...,
+            proxy: Url | None = None,
+            proxy_config: ProxyConfig | None = None,
+            cert_reqs: int | str | None = None,
+            assert_hostname: None | str | Literal[False] = None,
+            assert_fingerprint: str | None = None,
+            server_hostname: str | None = None,
+            ssl_context: ssl.SSLContext | None = None,
+            ca_certs: str | None = None,
+            ca_cert_dir: str | None = None,
+            ca_cert_data: None | str | bytes = None,
+            ssl_minimum_version: int | None = None,
+            ssl_maximum_version: int | None = None,
+            ssl_version: int | str | None = None,  # Deprecated
+            cert_file: str | None = None,
+            key_file: str | None = None,
+            key_password: str | None = None,
+        ) -> None:
+            ...

venv/lib/python3.10/site-packages/urllib3/_collections.py

@@ -0,0 +1,483 @@
+from __future__ import annotations
+
+import typing
+from collections import OrderedDict
+from enum import Enum, auto
+from threading import RLock
+
+if typing.TYPE_CHECKING:
+    # We can only import Protocol if TYPE_CHECKING because it's a development
+    # dependency, and is not available at runtime.
+    from typing import Protocol
+
+    from typing_extensions import Self
+
+    class HasGettableStringKeys(Protocol):
+        def keys(self) -> typing.Iterator[str]:
+            ...
+
+        def __getitem__(self, key: str) -> str:
+            ...
+
+
+__all__ = ["RecentlyUsedContainer", "HTTPHeaderDict"]
+
+
+# Key type
+_KT = typing.TypeVar("_KT")
+# Value type
+_VT = typing.TypeVar("_VT")
+# Default type
+_DT = typing.TypeVar("_DT")
+
+ValidHTTPHeaderSource = typing.Union[
+    "HTTPHeaderDict",
+    typing.Mapping[str, str],
+    typing.Iterable[typing.Tuple[str, str]],
+    "HasGettableStringKeys",
+]
+
+
+class _Sentinel(Enum):
+    not_passed = auto()
+
+
+def ensure_can_construct_http_header_dict(
+    potential: object,
+) -> ValidHTTPHeaderSource | None:
+    if isinstance(potential, HTTPHeaderDict):
+        return potential
+    elif isinstance(potential, typing.Mapping):
+        # Full runtime checking of the contents of a Mapping is expensive, so for the
+        # purposes of typechecking, we assume that any Mapping is the right shape.
+        return typing.cast(typing.Mapping[str, str], potential)
+    elif isinstance(potential, typing.Iterable):
+        # Similarly to Mapping, full runtime checking of the contents of an Iterable is
+        # expensive, so for the purposes of typechecking, we assume that any Iterable
+        # is the right shape.
+        return typing.cast(typing.Iterable[typing.Tuple[str, str]], potential)
+    elif hasattr(potential, "keys") and hasattr(potential, "__getitem__"):
+        return typing.cast("HasGettableStringKeys", potential)
+    else:
+        return None
+
+
+class RecentlyUsedContainer(typing.Generic[_KT, _VT], typing.MutableMapping[_KT, _VT]):
+    """
+    Provides a thread-safe dict-like container which maintains up to
+    ``maxsize`` keys while throwing away the least-recently-used keys beyond
+    ``maxsize``.
+
+    :param maxsize:
+        Maximum number of recent elements to retain.
+
+    :param dispose_func:
+        Every time an item is evicted from the container,
+        ``dispose_func(value)`` is called.  Callback which will get called
+    """
+
+    _container: typing.OrderedDict[_KT, _VT]
+    _maxsize: int
+    dispose_func: typing.Callable[[_VT], None] | None
+    lock: RLock
+
+    def __init__(
+        self,
+        maxsize: int = 10,
+        dispose_func: typing.Callable[[_VT], None] | None = None,
+    ) -> None:
+        super().__init__()
+        self._maxsize = maxsize
+        self.dispose_func = dispose_func
+        self._container = OrderedDict()
+        self.lock = RLock()
+
+    def __getitem__(self, key: _KT) -> _VT:
+        # Re-insert the item, moving it to the end of the eviction line.
+        with self.lock:
+            item = self._container.pop(key)
+            self._container[key] = item
+            return item
+
+    def __setitem__(self, key: _KT, value: _VT) -> None:
+        evicted_item = None
+        with self.lock:
+            # Possibly evict the existing value of 'key'
+            try:
+                # If the key exists, we'll overwrite it, which won't change the
+                # size of the pool. Because accessing a key should move it to
+                # the end of the eviction line, we pop it out first.
+                evicted_item = key, self._container.pop(key)
+                self._container[key] = value
+            except KeyError:
+                # When the key does not exist, we insert the value first so that
+                # evicting works in all cases, including when self._maxsize is 0
+                self._container[key] = value
+                if len(self._container) > self._maxsize:
+                    # If we didn't evict an existing value, and we've hit our maximum
+                    # size, then we have to evict the least recently used item from
+                    # the beginning of the container.
+                    evicted_item = self._container.popitem(last=False)
+
+        # After releasing the lock on the pool, dispose of any evicted value.
+        if evicted_item is not None and self.dispose_func:
+            _, evicted_value = evicted_item
+            self.dispose_func(evicted_value)
+
+    def __delitem__(self, key: _KT) -> None:
+        with self.lock:
+            value = self._container.pop(key)
+
+        if self.dispose_func:
+            self.dispose_func(value)
+
+    def __len__(self) -> int:
+        with self.lock:
+            return len(self._container)
+
+    def __iter__(self) -> typing.NoReturn:
+        raise NotImplementedError(
+            "Iteration over this class is unlikely to be threadsafe."
+        )
+
+    def clear(self) -> None:
+        with self.lock:
+            # Copy pointers to all values, then wipe the mapping
+            values = list(self._container.values())
+            self._container.clear()
+
+        if self.dispose_func:
+            for value in values:
+                self.dispose_func(value)
+
+    def keys(self) -> set[_KT]:  # type: ignore[override]
+        with self.lock:
+            return set(self._container.keys())
+
+
+class HTTPHeaderDictItemView(typing.Set[typing.Tuple[str, str]]):
+    """
+    HTTPHeaderDict is unusual for a Mapping[str, str] in that it has two modes of
+    address.
+
+    If we directly try to get an item with a particular name, we will get a string
+    back that is the concatenated version of all the values:
+
+    >>> d['X-Header-Name']
+    'Value1, Value2, Value3'
+
+    However, if we iterate over an HTTPHeaderDict's items, we will optionally combine
+    these values based on whether combine=True was called when building up the dictionary
+
+    >>> d = HTTPHeaderDict({"A": "1", "B": "foo"})
+    >>> d.add("A", "2", combine=True)
+    >>> d.add("B", "bar")
+    >>> list(d.items())
+    [
+        ('A', '1, 2'),
+        ('B', 'foo'),
+        ('B', 'bar'),
+    ]
+
+    This class conforms to the interface required by the MutableMapping ABC while
+    also giving us the nonstandard iteration behavior we want; items with duplicate
+    keys, ordered by time of first insertion.
+    """
+
+    _headers: HTTPHeaderDict
+
+    def __init__(self, headers: HTTPHeaderDict) -> None:
+        self._headers = headers
+
+    def __len__(self) -> int:
+        return len(list(self._headers.iteritems()))
+
+    def __iter__(self) -> typing.Iterator[tuple[str, str]]:
+        return self._headers.iteritems()
+
+    def __contains__(self, item: object) -> bool:
+        if isinstance(item, tuple) and len(item) == 2:
+            passed_key, passed_val = item
+            if isinstance(passed_key, str) and isinstance(passed_val, str):
+                return self._headers._has_value_for_header(passed_key, passed_val)
+        return False
+
+
+class HTTPHeaderDict(typing.MutableMapping[str, str]):
+    """
+    :param headers:
+        An iterable of field-value pairs. Must not contain multiple field names
+        when compared case-insensitively.
+
+    :param kwargs:
+        Additional field-value pairs to pass in to ``dict.update``.
+
+    A ``dict`` like container for storing HTTP Headers.
+
+    Field names are stored and compared case-insensitively in compliance with
+    RFC 7230. Iteration provides the first case-sensitive key seen for each
+    case-insensitive pair.
+
+    Using ``__setitem__`` syntax overwrites fields that compare equal
+    case-insensitively in order to maintain ``dict``'s api. For fields that
+    compare equal, instead create a new ``HTTPHeaderDict`` and use ``.add``
+    in a loop.
+
+    If multiple fields that are equal case-insensitively are passed to the
+    constructor or ``.update``, the behavior is undefined and some will be
+    lost.
+
+    >>> headers = HTTPHeaderDict()
+    >>> headers.add('Set-Cookie', 'foo=bar')
+    >>> headers.add('set-cookie', 'baz=quxx')
+    >>> headers['content-length'] = '7'
+    >>> headers['SET-cookie']
+    'foo=bar, baz=quxx'
+    >>> headers['Content-Length']
+    '7'
+    """
+
+    _container: typing.MutableMapping[str, list[str]]
+
+    def __init__(self, headers: ValidHTTPHeaderSource | None = None, **kwargs: str):
+        super().__init__()
+        self._container = {}  # 'dict' is insert-ordered
+        if headers is not None:
+            if isinstance(headers, HTTPHeaderDict):
+                self._copy_from(headers)
+            else:
+                self.extend(headers)
+        if kwargs:
+            self.extend(kwargs)
+
+    def __setitem__(self, key: str, val: str) -> None:
+        # avoid a bytes/str comparison by decoding before httplib
+        if isinstance(key, bytes):
+            key = key.decode("latin-1")
+        self._container[key.lower()] = [key, val]
+
+    def __getitem__(self, key: str) -> str:
+        val = self._container[key.lower()]
+        return ", ".join(val[1:])
+
+    def __delitem__(self, key: str) -> None:
+        del self._container[key.lower()]
+
+    def __contains__(self, key: object) -> bool:
+        if isinstance(key, str):
+            return key.lower() in self._container
+        return False
+
+    def setdefault(self, key: str, default: str = "") -> str:
+        return super().setdefault(key, default)
+
+    def __eq__(self, other: object) -> bool:
+        maybe_constructable = ensure_can_construct_http_header_dict(other)
+        if maybe_constructable is None:
+            return False
+        else:
+            other_as_http_header_dict = type(self)(maybe_constructable)
+
+        return {k.lower(): v for k, v in self.itermerged()} == {
+            k.lower(): v for k, v in other_as_http_header_dict.itermerged()
+        }
+
+    def __ne__(self, other: object) -> bool:
+        return not self.__eq__(other)
+
+    def __len__(self) -> int:
+        return len(self._container)
+
+    def __iter__(self) -> typing.Iterator[str]:
+        # Only provide the originally cased names
+        for vals in self._container.values():
+            yield vals[0]
+
+    def discard(self, key: str) -> None:
+        try:
+            del self[key]
+        except KeyError:
+            pass
+
+    def add(self, key: str, val: str, *, combine: bool = False) -> None:
+        """Adds a (name, value) pair, doesn't overwrite the value if it already
+        exists.
+
+        If this is called with combine=True, instead of adding a new header value
+        as a distinct item during iteration, this will instead append the value to
+        any existing header value with a comma. If no existing header value exists
+        for the key, then the value will simply be added, ignoring the combine parameter.
+
+        >>> headers = HTTPHeaderDict(foo='bar')
+        >>> headers.add('Foo', 'baz')
+        >>> headers['foo']
+        'bar, baz'
+        >>> list(headers.items())
+        [('foo', 'bar'), ('foo', 'baz')]
+        >>> headers.add('foo', 'quz', combine=True)
+        >>> list(headers.items())
+        [('foo', 'bar, baz, quz')]
+        """
+        # avoid a bytes/str comparison by decoding before httplib
+        if isinstance(key, bytes):
+            key = key.decode("latin-1")
+        key_lower = key.lower()
+        new_vals = [key, val]
+        # Keep the common case aka no item present as fast as possible
+        vals = self._container.setdefault(key_lower, new_vals)
+        if new_vals is not vals:
+            # if there are values here, then there is at least the initial
+            # key/value pair
+            assert len(vals) >= 2
+            if combine:
+                vals[-1] = vals[-1] + ", " + val
+            else:
+                vals.append(val)
+
+    def extend(self, *args: ValidHTTPHeaderSource, **kwargs: str) -> None:
+        """Generic import function for any type of header-like object.
+        Adapted version of MutableMapping.update in order to insert items
+        with self.add instead of self.__setitem__
+        """
+        if len(args) > 1:
+            raise TypeError(
+                f"extend() takes at most 1 positional arguments ({len(args)} given)"
+            )
+        other = args[0] if len(args) >= 1 else ()
+
+        if isinstance(other, HTTPHeaderDict):
+            for key, val in other.iteritems():
+                self.add(key, val)
+        elif isinstance(other, typing.Mapping):
+            for key, val in other.items():
+                self.add(key, val)
+        elif isinstance(other, typing.Iterable):
+            other = typing.cast(typing.Iterable[typing.Tuple[str, str]], other)
+            for key, value in other:
+                self.add(key, value)
+        elif hasattr(other, "keys") and hasattr(other, "__getitem__"):
+            # THIS IS NOT A TYPESAFE BRANCH
+            # In this branch, the object has a `keys` attr but is not a Mapping or any of
+            # the other types indicated in the method signature. We do some stuff with
+            # it as though it partially implements the Mapping interface, but we're not
+            # doing that stuff safely AT ALL.
+            for key in other.keys():
+                self.add(key, other[key])
+
+        for key, value in kwargs.items():
+            self.add(key, value)
+
+    @typing.overload
+    def getlist(self, key: str) -> list[str]:
+        ...
+
+    @typing.overload
+    def getlist(self, key: str, default: _DT) -> list[str] | _DT:
+        ...
+
+    def getlist(
+        self, key: str, default: _Sentinel | _DT = _Sentinel.not_passed
+    ) -> list[str] | _DT:
+        """Returns a list of all the values for the named field. Returns an
+        empty list if the key doesn't exist."""
+        try:
+            vals = self._container[key.lower()]
+        except KeyError:
+            if default is _Sentinel.not_passed:
+                # _DT is unbound; empty list is instance of List[str]
+                return []
+            # _DT is bound; default is instance of _DT
+            return default
+        else:
+            # _DT may or may not be bound; vals[1:] is instance of List[str], which
+            # meets our external interface requirement of `Union[List[str], _DT]`.
+            return vals[1:]
+
+    def _prepare_for_method_change(self) -> Self:
+        """
+        Remove content-specific header fields before changing the request
+        method to GET or HEAD according to RFC 9110, Section 15.4.
+        """
+        content_specific_headers = [
+            "Content-Encoding",
+            "Content-Language",
+            "Content-Location",
+            "Content-Type",
+            "Content-Length",
+            "Digest",
+            "Last-Modified",
+        ]
+        for header in content_specific_headers:
+            self.discard(header)
+        return self
+
+    # Backwards compatibility for httplib
+    getheaders = getlist
+    getallmatchingheaders = getlist
+    iget = getlist
+
+    # Backwards compatibility for http.cookiejar
+    get_all = getlist
+
+    def __repr__(self) -> str:
+        return f"{type(self).__name__}({dict(self.itermerged())})"
+
+    def _copy_from(self, other: HTTPHeaderDict) -> None:
+        for key in other:
+            val = other.getlist(key)
+            self._container[key.lower()] = [key, *val]
+
+    def copy(self) -> HTTPHeaderDict:
+        clone = type(self)()
+        clone._copy_from(self)
+        return clone
+
+    def iteritems(self) -> typing.Iterator[tuple[str, str]]:
+        """Iterate over all header lines, including duplicate ones."""
+        for key in self:
+            vals = self._container[key.lower()]
+            for val in vals[1:]:
+                yield vals[0], val
+
+    def itermerged(self) -> typing.Iterator[tuple[str, str]]:
+        """Iterate over all headers, merging duplicate ones together."""
+        for key in self:
+            val = self._container[key.lower()]
+            yield val[0], ", ".join(val[1:])
+
+    def items(self) -> HTTPHeaderDictItemView:  # type: ignore[override]
+        return HTTPHeaderDictItemView(self)
+
+    def _has_value_for_header(self, header_name: str, potential_value: str) -> bool:
+        if header_name in self:
+            return potential_value in self._container[header_name.lower()][1:]
+        return False
+
+    def __ior__(self, other: object) -> HTTPHeaderDict:
+        # Supports extending a header dict in-place using operator |=
+        # combining items with add instead of __setitem__
+        maybe_constructable = ensure_can_construct_http_header_dict(other)
+        if maybe_constructable is None:
+            return NotImplemented
+        self.extend(maybe_constructable)
+        return self
+
+    def __or__(self, other: object) -> HTTPHeaderDict:
+        # Supports merging header dicts using operator |
+        # combining items with add instead of __setitem__
+        maybe_constructable = ensure_can_construct_http_header_dict(other)
+        if maybe_constructable is None:
+            return NotImplemented
+        result = self.copy()
+        result.extend(maybe_constructable)
+        return result
+
+    def __ror__(self, other: object) -> HTTPHeaderDict:
+        # Supports merging header dicts using operator | when other is on left side
+        # combining items with add instead of __setitem__
+        maybe_constructable = ensure_can_construct_http_header_dict(other)
+        if maybe_constructable is None:
+            return NotImplemented
+        result = type(self)(maybe_constructable)
+        result.extend(self)
+        return result

venv/lib/python3.10/site-packages/urllib3/_request_methods.py

@@ -0,0 +1,279 @@
+from __future__ import annotations
+
+import json as _json
+import typing
+from urllib.parse import urlencode
+
+from ._base_connection import _TYPE_BODY
+from ._collections import HTTPHeaderDict
+from .filepost import _TYPE_FIELDS, encode_multipart_formdata
+from .response import BaseHTTPResponse
+
+__all__ = ["RequestMethods"]
+
+_TYPE_ENCODE_URL_FIELDS = typing.Union[
+    typing.Sequence[typing.Tuple[str, typing.Union[str, bytes]]],
+    typing.Mapping[str, typing.Union[str, bytes]],
+]
+
+
+class RequestMethods:
+    """
+    Convenience mixin for classes who implement a :meth:`urlopen` method, such
+    as :class:`urllib3.HTTPConnectionPool` and
+    :class:`urllib3.PoolManager`.
+
+    Provides behavior for making common types of HTTP request methods and
+    decides which type of request field encoding to use.
+
+    Specifically,
+
+    :meth:`.request_encode_url` is for sending requests whose fields are
+    encoded in the URL (such as GET, HEAD, DELETE).
+
+    :meth:`.request_encode_body` is for sending requests whose fields are
+    encoded in the *body* of the request using multipart or www-form-urlencoded
+    (such as for POST, PUT, PATCH).
+
+    :meth:`.request` is for making any kind of request, it will look up the
+    appropriate encoding format and use one of the above two methods to make
+    the request.
+
+    Initializer parameters:
+
+    :param headers:
+        Headers to include with all requests, unless other headers are given
+        explicitly.
+    """
+
+    _encode_url_methods = {"DELETE", "GET", "HEAD", "OPTIONS"}
+
+    def __init__(self, headers: typing.Mapping[str, str] | None = None) -> None:
+        self.headers = headers or {}
+
+    def urlopen(
+        self,
+        method: str,
+        url: str,
+        body: _TYPE_BODY | None = None,
+        headers: typing.Mapping[str, str] | None = None,
+        encode_multipart: bool = True,
+        multipart_boundary: str | None = None,
+        **kw: typing.Any,
+    ) -> BaseHTTPResponse:  # Abstract
+        raise NotImplementedError(
+            "Classes extending RequestMethods must implement "
+            "their own ``urlopen`` method."
+        )
+
+    def request(
+        self,
+        method: str,
+        url: str,
+        body: _TYPE_BODY | None = None,
+        fields: _TYPE_FIELDS | None = None,
+        headers: typing.Mapping[str, str] | None = None,
+        json: typing.Any | None = None,
+        **urlopen_kw: typing.Any,
+    ) -> BaseHTTPResponse:
+        """
+        Make a request using :meth:`urlopen` with the appropriate encoding of
+        ``fields`` based on the ``method`` used.
+
+        This is a convenience method that requires the least amount of manual
+        effort. It can be used in most situations, while still having the
+        option to drop down to more specific methods when necessary, such as
+        :meth:`request_encode_url`, :meth:`request_encode_body`,
+        or even the lowest level :meth:`urlopen`.
+
+        :param method:
+            HTTP request method (such as GET, POST, PUT, etc.)
+
+        :param url:
+            The URL to perform the request on.
+
+        :param body:
+            Data to send in the request body, either :class:`str`, :class:`bytes`,
+            an iterable of :class:`str`/:class:`bytes`, or a file-like object.
+
+        :param fields:
+            Data to encode and send in the request body.  Values are processed
+            by :func:`urllib.parse.urlencode`.
+
+        :param headers:
+            Dictionary of custom headers to send, such as User-Agent,
+            If-None-Match, etc. If None, pool headers are used. If provided,
+            these headers completely replace any pool-specific headers.
+
+        :param json:
+            Data to encode and send as JSON with UTF-encoded in the request body.
+            The ``"Content-Type"`` header will be set to ``"application/json"``
+            unless specified otherwise.
+        """
+        method = method.upper()
+
+        if json is not None and body is not None:
+            raise TypeError(
+                "request got values for both 'body' and 'json' parameters which are mutually exclusive"
+            )
+
+        if json is not None:
+            if headers is None:
+                headers = self.headers
+
+            if not ("content-type" in map(str.lower, headers.keys())):
+                headers = HTTPHeaderDict(headers)
+                headers["Content-Type"] = "application/json"
+
+            body = _json.dumps(json, separators=(",", ":"), ensure_ascii=False).encode(
+                "utf-8"
+            )
+
+        if body is not None:
+            urlopen_kw["body"] = body
+
+        if method in self._encode_url_methods:
+            return self.request_encode_url(
+                method,
+                url,
+                fields=fields,  # type: ignore[arg-type]
+                headers=headers,
+                **urlopen_kw,
+            )
+        else:
+            return self.request_encode_body(
+                method, url, fields=fields, headers=headers, **urlopen_kw
+            )
+
+    def request_encode_url(
+        self,
+        method: str,
+        url: str,
+        fields: _TYPE_ENCODE_URL_FIELDS | None = None,
+        headers: typing.Mapping[str, str] | None = None,
+        **urlopen_kw: str,
+    ) -> BaseHTTPResponse:
+        """
+        Make a request using :meth:`urlopen` with the ``fields`` encoded in
+        the url. This is useful for request methods like GET, HEAD, DELETE, etc.
+
+        :param method:
+            HTTP request method (such as GET, POST, PUT, etc.)
+
+        :param url:
+            The URL to perform the request on.
+
+        :param fields:
+            Data to encode and send in the request body.
+
+        :param headers:
+            Dictionary of custom headers to send, such as User-Agent,
+            If-None-Match, etc. If None, pool headers are used. If provided,
+            these headers completely replace any pool-specific headers.
+        """
+        if headers is None:
+            headers = self.headers
+
+        extra_kw: dict[str, typing.Any] = {"headers": headers}
+        extra_kw.update(urlopen_kw)
+
+        if fields:
+            url += "?" + urlencode(fields)
+
+        return self.urlopen(method, url, **extra_kw)
+
+    def request_encode_body(
+        self,
+        method: str,
+        url: str,
+        fields: _TYPE_FIELDS | None = None,
+        headers: typing.Mapping[str, str] | None = None,
+        encode_multipart: bool = True,
+        multipart_boundary: str | None = None,
+        **urlopen_kw: str,
+    ) -> BaseHTTPResponse:
+        """
+        Make a request using :meth:`urlopen` with the ``fields`` encoded in
+        the body. This is useful for request methods like POST, PUT, PATCH, etc.
+
+        When ``encode_multipart=True`` (default), then
+        :func:`urllib3.encode_multipart_formdata` is used to encode
+        the payload with the appropriate content type. Otherwise
+        :func:`urllib.parse.urlencode` is used with the
+        'application/x-www-form-urlencoded' content type.
+
+        Multipart encoding must be used when posting files, and it's reasonably
+        safe to use it in other times too. However, it may break request
+        signing, such as with OAuth.
+
+        Supports an optional ``fields`` parameter of key/value strings AND
+        key/filetuple. A filetuple is a (filename, data, MIME type) tuple where
+        the MIME type is optional. For example::
+
+            fields = {
+                'foo': 'bar',
+                'fakefile': ('foofile.txt', 'contents of foofile'),
+                'realfile': ('barfile.txt', open('realfile').read()),
+                'typedfile': ('bazfile.bin', open('bazfile').read(),
+                              'image/jpeg'),
+                'nonamefile': 'contents of nonamefile field',
+            }
+
+        When uploading a file, providing a filename (the first parameter of the
+        tuple) is optional but recommended to best mimic behavior of browsers.
+
+        Note that if ``headers`` are supplied, the 'Content-Type' header will
+        be overwritten because it depends on the dynamic random boundary string
+        which is used to compose the body of the request. The random boundary
+        string can be explicitly set with the ``multipart_boundary`` parameter.
+
+        :param method:
+            HTTP request method (such as GET, POST, PUT, etc.)
+
+        :param url:
+            The URL to perform the request on.
+
+        :param fields:
+            Data to encode and send in the request body.
+
+        :param headers:
+            Dictionary of custom headers to send, such as User-Agent,
+            If-None-Match, etc. If None, pool headers are used. If provided,
+            these headers completely replace any pool-specific headers.
+
+        :param encode_multipart:
+            If True, encode the ``fields`` using the multipart/form-data MIME
+            format.
+
+        :param multipart_boundary:
+            If not specified, then a random boundary will be generated using
+            :func:`urllib3.filepost.choose_boundary`.
+        """
+        if headers is None:
+            headers = self.headers
+
+        extra_kw: dict[str, typing.Any] = {"headers": HTTPHeaderDict(headers)}
+        body: bytes | str
+
+        if fields:
+            if "body" in urlopen_kw:
+                raise TypeError(
+                    "request got values for both 'fields' and 'body', can only specify one."
+                )
+
+            if encode_multipart:
+                body, content_type = encode_multipart_formdata(
+                    fields, boundary=multipart_boundary
+                )
+            else:
+                body, content_type = (
+                    urlencode(fields),  # type: ignore[arg-type]
+                    "application/x-www-form-urlencoded",
+                )
+
+            extra_kw["body"] = body
+            extra_kw["headers"].setdefault("Content-Type", content_type)
+
+        extra_kw.update(urlopen_kw)
+
+        return self.urlopen(method, url, **extra_kw)

venv/lib/python3.10/site-packages/urllib3/_version.py

@@ -0,0 +1,4 @@
+# This file is protected via CODEOWNERS
+from __future__ import annotations
+
+__version__ = "2.2.1"

venv/lib/python3.10/site-packages/urllib3/connection.py

@@ -0,0 +1,930 @@
+from __future__ import annotations
+
+import datetime
+import logging
+import os
+import re
+import socket
+import sys
+import typing
+import warnings
+from http.client import HTTPConnection as _HTTPConnection
+from http.client import HTTPException as HTTPException  # noqa: F401
+from http.client import ResponseNotReady
+from socket import timeout as SocketTimeout
+
+if typing.TYPE_CHECKING:
+    from typing import Literal
+
+    from .response import HTTPResponse
+    from .util.ssl_ import _TYPE_PEER_CERT_RET_DICT
+    from .util.ssltransport import SSLTransport
+
+from ._collections import HTTPHeaderDict
+from .util.response import assert_header_parsing
+from .util.timeout import _DEFAULT_TIMEOUT, _TYPE_TIMEOUT, Timeout
+from .util.util import to_str
+from .util.wait import wait_for_read
+
+try:  # Compiled with SSL?
+    import ssl
+
+    BaseSSLError = ssl.SSLError
+except (ImportError, AttributeError):
+    ssl = None  # type: ignore[assignment]
+
+    class BaseSSLError(BaseException):  # type: ignore[no-redef]
+        pass
+
+
+from ._base_connection import _TYPE_BODY
+from ._base_connection import ProxyConfig as ProxyConfig
+from ._base_connection import _ResponseOptions as _ResponseOptions
+from ._version import __version__
+from .exceptions import (
+    ConnectTimeoutError,
+    HeaderParsingError,
+    NameResolutionError,
+    NewConnectionError,
+    ProxyError,
+    SystemTimeWarning,
+)
+from .util import SKIP_HEADER, SKIPPABLE_HEADERS, connection, ssl_
+from .util.request import body_to_chunks
+from .util.ssl_ import assert_fingerprint as _assert_fingerprint
+from .util.ssl_ import (
+    create_urllib3_context,
+    is_ipaddress,
+    resolve_cert_reqs,
+    resolve_ssl_version,
+    ssl_wrap_socket,
+)
+from .util.ssl_match_hostname import CertificateError, match_hostname
+from .util.url import Url
+
+# Not a no-op, we're adding this to the namespace so it can be imported.
+ConnectionError = ConnectionError
+BrokenPipeError = BrokenPipeError
+
+
+log = logging.getLogger(__name__)
+
+port_by_scheme = {"http": 80, "https": 443}
+
+# When it comes time to update this value as a part of regular maintenance
+# (ie test_recent_date is failing) update it to ~6 months before the current date.
+RECENT_DATE = datetime.date(2023, 6, 1)
+
+_CONTAINS_CONTROL_CHAR_RE = re.compile(r"[^-!#$%&'*+.^_`|~0-9a-zA-Z]")
+
+_HAS_SYS_AUDIT = hasattr(sys, "audit")
+
+
+class HTTPConnection(_HTTPConnection):
+    """
+    Based on :class:`http.client.HTTPConnection` but provides an extra constructor
+    backwards-compatibility layer between older and newer Pythons.
+
+    Additional keyword parameters are used to configure attributes of the connection.
+    Accepted parameters include:
+
+    - ``source_address``: Set the source address for the current connection.
+    - ``socket_options``: Set specific options on the underlying socket. If not specified, then
+      defaults are loaded from ``HTTPConnection.default_socket_options`` which includes disabling
+      Nagle's algorithm (sets TCP_NODELAY to 1) unless the connection is behind a proxy.
+
+      For example, if you wish to enable TCP Keep Alive in addition to the defaults,
+      you might pass:
+
+      .. code-block:: python
+
+         HTTPConnection.default_socket_options + [
+             (socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1),
+         ]
+
+      Or you may want to disable the defaults by passing an empty list (e.g., ``[]``).
+    """
+
+    default_port: typing.ClassVar[int] = port_by_scheme["http"]  # type: ignore[misc]
+
+    #: Disable Nagle's algorithm by default.
+    #: ``[(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)]``
+    default_socket_options: typing.ClassVar[connection._TYPE_SOCKET_OPTIONS] = [
+        (socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
+    ]
+
+    #: Whether this connection verifies the host's certificate.
+    is_verified: bool = False
+
+    #: Whether this proxy connection verified the proxy host's certificate.
+    # If no proxy is currently connected to the value will be ``None``.
+    proxy_is_verified: bool | None = None
+
+    blocksize: int
+    source_address: tuple[str, int] | None
+    socket_options: connection._TYPE_SOCKET_OPTIONS | None
+
+    _has_connected_to_proxy: bool
+    _response_options: _ResponseOptions | None
+    _tunnel_host: str | None
+    _tunnel_port: int | None
+    _tunnel_scheme: str | None
+
+    def __init__(
+        self,
+        host: str,
+        port: int | None = None,
+        *,
+        timeout: _TYPE_TIMEOUT = _DEFAULT_TIMEOUT,
+        source_address: tuple[str, int] | None = None,
+        blocksize: int = 16384,
+        socket_options: None
+        | (connection._TYPE_SOCKET_OPTIONS) = default_socket_options,
+        proxy: Url | None = None,
+        proxy_config: ProxyConfig | None = None,
+    ) -> None:
+        super().__init__(
+            host=host,
+            port=port,
+            timeout=Timeout.resolve_default_timeout(timeout),
+            source_address=source_address,
+            blocksize=blocksize,
+        )
+        self.socket_options = socket_options
+        self.proxy = proxy
+        self.proxy_config = proxy_config
+
+        self._has_connected_to_proxy = False
+        self._response_options = None
+        self._tunnel_host: str | None = None
+        self._tunnel_port: int | None = None
+        self._tunnel_scheme: str | None = None
+
+    @property
+    def host(self) -> str:
+        """
+        Getter method to remove any trailing dots that indicate the hostname is an FQDN.
+
+        In general, SSL certificates don't include the trailing dot indicating a
+        fully-qualified domain name, and thus, they don't validate properly when
+        checked against a domain name that includes the dot. In addition, some
+        servers may not expect to receive the trailing dot when provided.
+
+        However, the hostname with trailing dot is critical to DNS resolution; doing a
+        lookup with the trailing dot will properly only resolve the appropriate FQDN,
+        whereas a lookup without a trailing dot will search the system's search domain
+        list. Thus, it's important to keep the original host around for use only in
+        those cases where it's appropriate (i.e., when doing DNS lookup to establish the
+        actual TCP connection across which we're going to send HTTP requests).
+        """
+        return self._dns_host.rstrip(".")
+
+    @host.setter
+    def host(self, value: str) -> None:
+        """
+        Setter for the `host` property.
+
+        We assume that only urllib3 uses the _dns_host attribute; httplib itself
+        only uses `host`, and it seems reasonable that other libraries follow suit.
+        """
+        self._dns_host = value
+
+    def _new_conn(self) -> socket.socket:
+        """Establish a socket connection and set nodelay settings on it.
+
+        :return: New socket connection.
+        """
+        try:
+            sock = connection.create_connection(
+                (self._dns_host, self.port),
+                self.timeout,
+                source_address=self.source_address,
+                socket_options=self.socket_options,
+            )
+        except socket.gaierror as e:
+            raise NameResolutionError(self.host, self, e) from e
+        except SocketTimeout as e:
+            raise ConnectTimeoutError(
+                self,
+                f"Connection to {self.host} timed out. (connect timeout={self.timeout})",
+            ) from e
+
+        except OSError as e:
+            raise NewConnectionError(
+                self, f"Failed to establish a new connection: {e}"
+            ) from e
+
+        # Audit hooks are only available in Python 3.8+
+        if _HAS_SYS_AUDIT:
+            sys.audit("http.client.connect", self, self.host, self.port)
+
+        return sock
+
+    def set_tunnel(
+        self,
+        host: str,
+        port: int | None = None,
+        headers: typing.Mapping[str, str] | None = None,
+        scheme: str = "http",
+    ) -> None:
+        if scheme not in ("http", "https"):
+            raise ValueError(
+                f"Invalid proxy scheme for tunneling: {scheme!r}, must be either 'http' or 'https'"
+            )
+        super().set_tunnel(host, port=port, headers=headers)
+        self._tunnel_scheme = scheme
+
+    def connect(self) -> None:
+        self.sock = self._new_conn()
+        if self._tunnel_host:
+            # If we're tunneling it means we're connected to our proxy.
+            self._has_connected_to_proxy = True
+
+            # TODO: Fix tunnel so it doesn't depend on self.sock state.
+            self._tunnel()  # type: ignore[attr-defined]
+
+        # If there's a proxy to be connected to we are fully connected.
+        # This is set twice (once above and here) due to forwarding proxies
+        # not using tunnelling.
+        self._has_connected_to_proxy = bool(self.proxy)
+
+        if self._has_connected_to_proxy:
+            self.proxy_is_verified = False
+
+    @property
+    def is_closed(self) -> bool:
+        return self.sock is None
+
+    @property
+    def is_connected(self) -> bool:
+        if self.sock is None:
+            return False
+        return not wait_for_read(self.sock, timeout=0.0)
+
+    @property
+    def has_connected_to_proxy(self) -> bool:
+        return self._has_connected_to_proxy
+
+    @property
+    def proxy_is_forwarding(self) -> bool:
+        """
+        Return True if a forwarding proxy is configured, else return False
+        """
+        return bool(self.proxy) and self._tunnel_host is None
+
+    def close(self) -> None:
+        try:
+            super().close()
+        finally:
+            # Reset all stateful properties so connection
+            # can be re-used without leaking prior configs.
+            self.sock = None
+            self.is_verified = False
+            self.proxy_is_verified = None
+            self._has_connected_to_proxy = False
+            self._response_options = None
+            self._tunnel_host = None
+            self._tunnel_port = None
+            self._tunnel_scheme = None
+
+    def putrequest(
+        self,
+        method: str,
+        url: str,
+        skip_host: bool = False,
+        skip_accept_encoding: bool = False,
+    ) -> None:
+        """"""
+        # Empty docstring because the indentation of CPython's implementation
+        # is broken but we don't want this method in our documentation.
+        match = _CONTAINS_CONTROL_CHAR_RE.search(method)
+        if match:
+            raise ValueError(
+                f"Method cannot contain non-token characters {method!r} (found at least {match.group()!r})"
+            )
+
+        return super().putrequest(
+            method, url, skip_host=skip_host, skip_accept_encoding=skip_accept_encoding
+        )
+
+    def putheader(self, header: str, *values: str) -> None:  # type: ignore[override]
+        """"""
+        if not any(isinstance(v, str) and v == SKIP_HEADER for v in values):
+            super().putheader(header, *values)
+        elif to_str(header.lower()) not in SKIPPABLE_HEADERS:
+            skippable_headers = "', '".join(
+                [str.title(header) for header in sorted(SKIPPABLE_HEADERS)]
+            )
+            raise ValueError(
+                f"urllib3.util.SKIP_HEADER only supports '{skippable_headers}'"
+            )
+
+    # `request` method's signature intentionally violates LSP.
+    # urllib3's API is different from `http.client.HTTPConnection` and the subclassing is only incidental.
+    def request(  # type: ignore[override]
+        self,
+        method: str,
+        url: str,
+        body: _TYPE_BODY | None = None,
+        headers: typing.Mapping[str, str] | None = None,
+        *,
+        chunked: bool = False,
+        preload_content: bool = True,
+        decode_content: bool = True,
+        enforce_content_length: bool = True,
+    ) -> None:
+        # Update the inner socket's timeout value to send the request.
+        # This only triggers if the connection is re-used.
+        if self.sock is not None:
+            self.sock.settimeout(self.timeout)
+
+        # Store these values to be fed into the HTTPResponse
+        # object later. TODO: Remove this in favor of a real
+        # HTTP lifecycle mechanism.
+
+        # We have to store these before we call .request()
+        # because sometimes we can still salvage a response
+        # off the wire even if we aren't able to completely
+        # send the request body.
+        self._response_options = _ResponseOptions(
+            request_method=method,
+            request_url=url,
+            preload_content=preload_content,
+            decode_content=decode_content,
+            enforce_content_length=enforce_content_length,
+        )
+
+        if headers is None:
+            headers = {}
+        header_keys = frozenset(to_str(k.lower()) for k in headers)
+        skip_accept_encoding = "accept-encoding" in header_keys
+        skip_host = "host" in header_keys
+        self.putrequest(
+            method, url, skip_accept_encoding=skip_accept_encoding, skip_host=skip_host
+        )
+
+        # Transform the body into an iterable of sendall()-able chunks
+        # and detect if an explicit Content-Length is doable.
+        chunks_and_cl = body_to_chunks(body, method=method, blocksize=self.blocksize)
+        chunks = chunks_and_cl.chunks
+        content_length = chunks_and_cl.content_length
+
+        # When chunked is explicit set to 'True' we respect that.
+        if chunked:
+            if "transfer-encoding" not in header_keys:
+                self.putheader("Transfer-Encoding", "chunked")
+        else:
+            # Detect whether a framing mechanism is already in use. If so
+            # we respect that value, otherwise we pick chunked vs content-length
+            # depending on the type of 'body'.
+            if "content-length" in header_keys:
+                chunked = False
+            elif "transfer-encoding" in header_keys:
+                chunked = True
+
+            # Otherwise we go off the recommendation of 'body_to_chunks()'.
+            else:
+                chunked = False
+                if content_length is None:
+                    if chunks is not None:
+                        chunked = True
+                        self.putheader("Transfer-Encoding", "chunked")
+                else:
+                    self.putheader("Content-Length", str(content_length))
+
+        # Now that framing headers are out of the way we send all the other headers.
+        if "user-agent" not in header_keys:
+            self.putheader("User-Agent", _get_default_user_agent())
+        for header, value in headers.items():
+            self.putheader(header, value)
+        self.endheaders()
+
+        # If we're given a body we start sending that in chunks.
+        if chunks is not None:
+            for chunk in chunks:
+                # Sending empty chunks isn't allowed for TE: chunked
+                # as it indicates the end of the body.
+                if not chunk:
+                    continue
+                if isinstance(chunk, str):
+                    chunk = chunk.encode("utf-8")
+                if chunked:
+                    self.send(b"%x\r\n%b\r\n" % (len(chunk), chunk))
+                else:
+                    self.send(chunk)
+
+        # Regardless of whether we have a body or not, if we're in
+        # chunked mode we want to send an explicit empty chunk.
+        if chunked:
+            self.send(b"0\r\n\r\n")
+
+    def request_chunked(
+        self,
+        method: str,
+        url: str,
+        body: _TYPE_BODY | None = None,
+        headers: typing.Mapping[str, str] | None = None,
+    ) -> None:
+        """
+        Alternative to the common request method, which sends the
+        body with chunked encoding and not as one block
+        """
+        warnings.warn(
+            "HTTPConnection.request_chunked() is deprecated and will be removed "
+            "in urllib3 v2.1.0. Instead use HTTPConnection.request(..., chunked=True).",
+            category=DeprecationWarning,
+            stacklevel=2,
+        )
+        self.request(method, url, body=body, headers=headers, chunked=True)
+
+    def getresponse(  # type: ignore[override]
+        self,
+    ) -> HTTPResponse:
+        """
+        Get the response from the server.
+
+        If the HTTPConnection is in the correct state, returns an instance of HTTPResponse or of whatever object is returned by the response_class variable.
+
+        If a request has not been sent or if a previous response has not be handled, ResponseNotReady is raised. If the HTTP response indicates that the connection should be closed, then it will be closed before the response is returned. When the connection is closed, the underlying socket is closed.
+        """
+        # Raise the same error as http.client.HTTPConnection
+        if self._response_options is None:
+            raise ResponseNotReady()
+
+        # Reset this attribute for being used again.
+        resp_options = self._response_options
+        self._response_options = None
+
+        # Since the connection's timeout value may have been updated
+        # we need to set the timeout on the socket.
+        self.sock.settimeout(self.timeout)
+
+        # This is needed here to avoid circular import errors
+        from .response import HTTPResponse
+
+        # Get the response from http.client.HTTPConnection
+        httplib_response = super().getresponse()
+
+        try:
+            assert_header_parsing(httplib_response.msg)
+        except (HeaderParsingError, TypeError) as hpe:
+            log.warning(
+                "Failed to parse headers (url=%s): %s",
+                _url_from_connection(self, resp_options.request_url),
+                hpe,
+                exc_info=True,
+            )
+
+        headers = HTTPHeaderDict(httplib_response.msg.items())
+
+        response = HTTPResponse(
+            body=httplib_response,
+            headers=headers,
+            status=httplib_response.status,
+            version=httplib_response.version,
+            reason=httplib_response.reason,
+            preload_content=resp_options.preload_content,
+            decode_content=resp_options.decode_content,
+            original_response=httplib_response,
+            enforce_content_length=resp_options.enforce_content_length,
+            request_method=resp_options.request_method,
+            request_url=resp_options.request_url,
+        )
+        return response
+
+
+class HTTPSConnection(HTTPConnection):
+    """
+    Many of the parameters to this constructor are passed to the underlying SSL
+    socket by means of :py:func:`urllib3.util.ssl_wrap_socket`.
+    """
+
+    default_port = port_by_scheme["https"]  # type: ignore[misc]
+
+    cert_reqs: int | str | None = None
+    ca_certs: str | None = None
+    ca_cert_dir: str | None = None
+    ca_cert_data: None | str | bytes = None
+    ssl_version: int | str | None = None
+    ssl_minimum_version: int | None = None
+    ssl_maximum_version: int | None = None
+    assert_fingerprint: str | None = None
+
+    def __init__(
+        self,
+        host: str,
+        port: int | None = None,
+        *,
+        timeout: _TYPE_TIMEOUT = _DEFAULT_TIMEOUT,
+        source_address: tuple[str, int] | None = None,
+        blocksize: int = 16384,
+        socket_options: None
+        | (connection._TYPE_SOCKET_OPTIONS) = HTTPConnection.default_socket_options,
+        proxy: Url | None = None,
+        proxy_config: ProxyConfig | None = None,
+        cert_reqs: int | str | None = None,
+        assert_hostname: None | str | Literal[False] = None,
+        assert_fingerprint: str | None = None,
+        server_hostname: str | None = None,
+        ssl_context: ssl.SSLContext | None = None,
+        ca_certs: str | None = None,
+        ca_cert_dir: str | None = None,
+        ca_cert_data: None | str | bytes = None,
+        ssl_minimum_version: int | None = None,
+        ssl_maximum_version: int | None = None,
+        ssl_version: int | str | None = None,  # Deprecated
+        cert_file: str | None = None,
+        key_file: str | None = None,
+        key_password: str | None = None,
+    ) -> None:
+        super().__init__(
+            host,
+            port=port,
+            timeout=timeout,
+            source_address=source_address,
+            blocksize=blocksize,
+            socket_options=socket_options,
+            proxy=proxy,
+            proxy_config=proxy_config,
+        )
+
+        self.key_file = key_file
+        self.cert_file = cert_file
+        self.key_password = key_password
+        self.ssl_context = ssl_context
+        self.server_hostname = server_hostname
+        self.assert_hostname = assert_hostname
+        self.assert_fingerprint = assert_fingerprint
+        self.ssl_version = ssl_version
+        self.ssl_minimum_version = ssl_minimum_version
+        self.ssl_maximum_version = ssl_maximum_version
+        self.ca_certs = ca_certs and os.path.expanduser(ca_certs)
+        self.ca_cert_dir = ca_cert_dir and os.path.expanduser(ca_cert_dir)
+        self.ca_cert_data = ca_cert_data
+
+        # cert_reqs depends on ssl_context so calculate last.
+        if cert_reqs is None:
+            if self.ssl_context is not None:
+                cert_reqs = self.ssl_context.verify_mode
+            else:
+                cert_reqs = resolve_cert_reqs(None)
+        self.cert_reqs = cert_reqs
+
+    def set_cert(
+        self,
+        key_file: str | None = None,
+        cert_file: str | None = None,
+        cert_reqs: int | str | None = None,
+        key_password: str | None = None,
+        ca_certs: str | None = None,
+        assert_hostname: None | str | Literal[False] = None,
+        assert_fingerprint: str | None = None,
+        ca_cert_dir: str | None = None,
+        ca_cert_data: None | str | bytes = None,
+    ) -> None:
+        """
+        This method should only be called once, before the connection is used.
+        """
+        warnings.warn(
+            "HTTPSConnection.set_cert() is deprecated and will be removed "
+            "in urllib3 v2.1.0. Instead provide the parameters to the "
+            "HTTPSConnection constructor.",
+            category=DeprecationWarning,
+            stacklevel=2,
+        )
+
+        # If cert_reqs is not provided we'll assume CERT_REQUIRED unless we also
+        # have an SSLContext object in which case we'll use its verify_mode.
+        if cert_reqs is None:
+            if self.ssl_context is not None:
+                cert_reqs = self.ssl_context.verify_mode
+            else:
+                cert_reqs = resolve_cert_reqs(None)
+
+        self.key_file = key_file
+        self.cert_file = cert_file
+        self.cert_reqs = cert_reqs
+        self.key_password = key_password
+        self.assert_hostname = assert_hostname
+        self.assert_fingerprint = assert_fingerprint
+        self.ca_certs = ca_certs and os.path.expanduser(ca_certs)
+        self.ca_cert_dir = ca_cert_dir and os.path.expanduser(ca_cert_dir)
+        self.ca_cert_data = ca_cert_data
+
+    def connect(self) -> None:
+        sock: socket.socket | ssl.SSLSocket
+        self.sock = sock = self._new_conn()
+        server_hostname: str = self.host
+        tls_in_tls = False
+
+        # Do we need to establish a tunnel?
+        if self._tunnel_host is not None:
+            # We're tunneling to an HTTPS origin so need to do TLS-in-TLS.
+            if self._tunnel_scheme == "https":
+                # _connect_tls_proxy will verify and assign proxy_is_verified
+                self.sock = sock = self._connect_tls_proxy(self.host, sock)
+                tls_in_tls = True
+            elif self._tunnel_scheme == "http":
+                self.proxy_is_verified = False
+
+            # If we're tunneling it means we're connected to our proxy.
+            self._has_connected_to_proxy = True
+
+            self._tunnel()  # type: ignore[attr-defined]
+            # Override the host with the one we're requesting data from.
+            server_hostname = self._tunnel_host
+
+        if self.server_hostname is not None:
+            server_hostname = self.server_hostname
+
+        is_time_off = datetime.date.today() < RECENT_DATE
+        if is_time_off:
+            warnings.warn(
+                (
+                    f"System time is way off (before {RECENT_DATE}). This will probably "
+                    "lead to SSL verification errors"
+                ),
+                SystemTimeWarning,
+            )
+
+        # Remove trailing '.' from fqdn hostnames to allow certificate validation
+        server_hostname_rm_dot = server_hostname.rstrip(".")
+
+        sock_and_verified = _ssl_wrap_socket_and_match_hostname(
+            sock=sock,
+            cert_reqs=self.cert_reqs,
+            ssl_version=self.ssl_version,
+            ssl_minimum_version=self.ssl_minimum_version,
+            ssl_maximum_version=self.ssl_maximum_version,
+            ca_certs=self.ca_certs,
+            ca_cert_dir=self.ca_cert_dir,
+            ca_cert_data=self.ca_cert_data,
+            cert_file=self.cert_file,
+            key_file=self.key_file,
+            key_password=self.key_password,
+            server_hostname=server_hostname_rm_dot,
+            ssl_context=self.ssl_context,
+            tls_in_tls=tls_in_tls,
+            assert_hostname=self.assert_hostname,
+            assert_fingerprint=self.assert_fingerprint,
+        )
+        self.sock = sock_and_verified.socket
+
+        # Forwarding proxies can never have a verified target since
+        # the proxy is the one doing the verification. Should instead
+        # use a CONNECT tunnel in order to verify the target.
+        # See: https://github.com/urllib3/urllib3/issues/3267.
+        if self.proxy_is_forwarding:
+            self.is_verified = False
+        else:
+            self.is_verified = sock_and_verified.is_verified
+
+        # If there's a proxy to be connected to we are fully connected.
+        # This is set twice (once above and here) due to forwarding proxies
+        # not using tunnelling.
+        self._has_connected_to_proxy = bool(self.proxy)
+
+        # Set `self.proxy_is_verified` unless it's already set while
+        # establishing a tunnel.
+        if self._has_connected_to_proxy and self.proxy_is_verified is None:
+            self.proxy_is_verified = sock_and_verified.is_verified
+
+    def _connect_tls_proxy(self, hostname: str, sock: socket.socket) -> ssl.SSLSocket:
+        """
+        Establish a TLS connection to the proxy using the provided SSL context.
+        """
+        # `_connect_tls_proxy` is called when self._tunnel_host is truthy.
+        proxy_config = typing.cast(ProxyConfig, self.proxy_config)
+        ssl_context = proxy_config.ssl_context
+        sock_and_verified = _ssl_wrap_socket_and_match_hostname(
+            sock,
+            cert_reqs=self.cert_reqs,
+            ssl_version=self.ssl_version,
+            ssl_minimum_version=self.ssl_minimum_version,
+            ssl_maximum_version=self.ssl_maximum_version,
+            ca_certs=self.ca_certs,
+            ca_cert_dir=self.ca_cert_dir,
+            ca_cert_data=self.ca_cert_data,
+            server_hostname=hostname,
+            ssl_context=ssl_context,
+            assert_hostname=proxy_config.assert_hostname,
+            assert_fingerprint=proxy_config.assert_fingerprint,
+            # Features that aren't implemented for proxies yet:
+            cert_file=None,
+            key_file=None,
+            key_password=None,
+            tls_in_tls=False,
+        )
+        self.proxy_is_verified = sock_and_verified.is_verified
+        return sock_and_verified.socket  # type: ignore[return-value]
+
+
+class _WrappedAndVerifiedSocket(typing.NamedTuple):
+    """
+    Wrapped socket and whether the connection is
+    verified after the TLS handshake
+    """
+
+    socket: ssl.SSLSocket | SSLTransport
+    is_verified: bool
+
+
+def _ssl_wrap_socket_and_match_hostname(
+    sock: socket.socket,
+    *,
+    cert_reqs: None | str | int,
+    ssl_version: None | str | int,
+    ssl_minimum_version: int | None,
+    ssl_maximum_version: int | None,
+    cert_file: str | None,
+    key_file: str | None,
+    key_password: str | None,
+    ca_certs: str | None,
+    ca_cert_dir: str | None,
+    ca_cert_data: None | str | bytes,
+    assert_hostname: None | str | Literal[False],
+    assert_fingerprint: str | None,
+    server_hostname: str | None,
+    ssl_context: ssl.SSLContext | None,
+    tls_in_tls: bool = False,
+) -> _WrappedAndVerifiedSocket:
+    """Logic for constructing an SSLContext from all TLS parameters, passing
+    that down into ssl_wrap_socket, and then doing certificate verification
+    either via hostname or fingerprint. This function exists to guarantee
+    that both proxies and targets have the same behavior when connecting via TLS.
+    """
+    default_ssl_context = False
+    if ssl_context is None:
+        default_ssl_context = True
+        context = create_urllib3_context(
+            ssl_version=resolve_ssl_version(ssl_version),
+            ssl_minimum_version=ssl_minimum_version,
+            ssl_maximum_version=ssl_maximum_version,
+            cert_reqs=resolve_cert_reqs(cert_reqs),
+        )
+    else:
+        context = ssl_context
+
+    context.verify_mode = resolve_cert_reqs(cert_reqs)
+
+    # In some cases, we want to verify hostnames ourselves
+    if (
+        # `ssl` can't verify fingerprints or alternate hostnames
+        assert_fingerprint
+        or assert_hostname
+        # assert_hostname can be set to False to disable hostname checking
+        or assert_hostname is False
+        # We still support OpenSSL 1.0.2, which prevents us from verifying
+        # hostnames easily: https://github.com/pyca/pyopenssl/pull/933
+        or ssl_.IS_PYOPENSSL
+        or not ssl_.HAS_NEVER_CHECK_COMMON_NAME
+    ):
+        context.check_hostname = False
+
+    # Try to load OS default certs if none are given. We need to do the hasattr() check
+    # for custom pyOpenSSL SSLContext objects because they don't support
+    # load_default_certs().
+    if (
+        not ca_certs
+        and not ca_cert_dir
+        and not ca_cert_data
+        and default_ssl_context
+        and hasattr(context, "load_default_certs")
+    ):
+        context.load_default_certs()
+
+    # Ensure that IPv6 addresses are in the proper format and don't have a
+    # scope ID. Python's SSL module fails to recognize scoped IPv6 addresses
+    # and interprets them as DNS hostnames.
+    if server_hostname is not None:
+        normalized = server_hostname.strip("[]")
+        if "%" in normalized:
+            normalized = normalized[: normalized.rfind("%")]
+        if is_ipaddress(normalized):
+            server_hostname = normalized
+
+    ssl_sock = ssl_wrap_socket(
+        sock=sock,
+        keyfile=key_file,
+        certfile=cert_file,
+        key_password=key_password,
+        ca_certs=ca_certs,
+        ca_cert_dir=ca_cert_dir,
+        ca_cert_data=ca_cert_data,
+        server_hostname=server_hostname,
+        ssl_context=context,
+        tls_in_tls=tls_in_tls,
+    )
+
+    try:
+        if assert_fingerprint:
+            _assert_fingerprint(
+                ssl_sock.getpeercert(binary_form=True), assert_fingerprint
+            )
+        elif (
+            context.verify_mode != ssl.CERT_NONE
+            and not context.check_hostname
+            and assert_hostname is not False
+        ):
+            cert: _TYPE_PEER_CERT_RET_DICT = ssl_sock.getpeercert()  # type: ignore[assignment]
+
+            # Need to signal to our match_hostname whether to use 'commonName' or not.
+            # If we're using our own constructed SSLContext we explicitly set 'False'
+            # because PyPy hard-codes 'True' from SSLContext.hostname_checks_common_name.
+            if default_ssl_context:
+                hostname_checks_common_name = False
+            else:
+                hostname_checks_common_name = (
+                    getattr(context, "hostname_checks_common_name", False) or False
+                )
+
+            _match_hostname(
+                cert,
+                assert_hostname or server_hostname,  # type: ignore[arg-type]
+                hostname_checks_common_name,
+            )
+
+        return _WrappedAndVerifiedSocket(
+            socket=ssl_sock,
+            is_verified=context.verify_mode == ssl.CERT_REQUIRED
+            or bool(assert_fingerprint),
+        )
+    except BaseException:
+        ssl_sock.close()
+        raise
+
+
+def _match_hostname(
+    cert: _TYPE_PEER_CERT_RET_DICT | None,
+    asserted_hostname: str,
+    hostname_checks_common_name: bool = False,
+) -> None:
+    # Our upstream implementation of ssl.match_hostname()
+    # only applies this normalization to IP addresses so it doesn't
+    # match DNS SANs so we do the same thing!
+    stripped_hostname = asserted_hostname.strip("[]")
+    if is_ipaddress(stripped_hostname):
+        asserted_hostname = stripped_hostname
+
+    try:
+        match_hostname(cert, asserted_hostname, hostname_checks_common_name)
+    except CertificateError as e:
+        log.warning(
+            "Certificate did not match expected hostname: %s. Certificate: %s",
+            asserted_hostname,
+            cert,
+        )
+        # Add cert to exception and reraise so client code can inspect
+        # the cert when catching the exception, if they want to
+        e._peer_cert = cert  # type: ignore[attr-defined]
+        raise
+
+
+def _wrap_proxy_error(err: Exception, proxy_scheme: str | None) -> ProxyError:
+    # Look for the phrase 'wrong version number', if found
+    # then we should warn the user that we're very sure that
+    # this proxy is HTTP-only and they have a configuration issue.
+    error_normalized = " ".join(re.split("[^a-z]", str(err).lower()))
+    is_likely_http_proxy = (
+        "wrong version number" in error_normalized
+        or "unknown protocol" in error_normalized
+        or "record layer failure" in error_normalized
+    )
+    http_proxy_warning = (
+        ". Your proxy appears to only use HTTP and not HTTPS, "
+        "try changing your proxy URL to be HTTP. See: "
+        "https://urllib3.readthedocs.io/en/latest/advanced-usage.html"
+        "#https-proxy-error-http-proxy"
+    )
+    new_err = ProxyError(
+        f"Unable to connect to proxy"
+        f"{http_proxy_warning if is_likely_http_proxy and proxy_scheme == 'https' else ''}",
+        err,
+    )
+    new_err.__cause__ = err
+    return new_err
+
+
+def _get_default_user_agent() -> str:
+    return f"python-urllib3/{__version__}"
+
+
+class DummyConnection:
+    """Used to detect a failed ConnectionCls import."""
+
+
+if not ssl:
+    HTTPSConnection = DummyConnection  # type: ignore[misc, assignment] # noqa: F811
+
+
+VerifiedHTTPSConnection = HTTPSConnection
+
+
+def _url_from_connection(
+    conn: HTTPConnection | HTTPSConnection, path: str | None = None
+) -> str:
+    """Returns the URL from a given connection. This is mainly used for testing and logging."""
+
+    scheme = "https" if isinstance(conn, HTTPSConnection) else "http"
+
+    return Url(scheme=scheme, host=conn.host, port=conn.port, path=path).url

venv/lib/python3.10/site-packages/urllib3/connectionpool.py

@@ -0,0 +1,1186 @@
+from __future__ import annotations
+
+import errno
+import logging
+import queue
+import sys
+import typing
+import warnings
+import weakref
+from socket import timeout as SocketTimeout
+from types import TracebackType
+
+from ._base_connection import _TYPE_BODY
+from ._collections import HTTPHeaderDict
+from ._request_methods import RequestMethods
+from .connection import (
+    BaseSSLError,
+    BrokenPipeError,
+    DummyConnection,
+    HTTPConnection,
+    HTTPException,
+    HTTPSConnection,
+    ProxyConfig,
+    _wrap_proxy_error,
+)
+from .connection import port_by_scheme as port_by_scheme
+from .exceptions import (
+    ClosedPoolError,
+    EmptyPoolError,
+    FullPoolError,
+    HostChangedError,
+    InsecureRequestWarning,
+    LocationValueError,
+    MaxRetryError,
+    NewConnectionError,
+    ProtocolError,
+    ProxyError,
+    ReadTimeoutError,
+    SSLError,
+    TimeoutError,
+)
+from .response import BaseHTTPResponse
+from .util.connection import is_connection_dropped
+from .util.proxy import connection_requires_http_tunnel
+from .util.request import _TYPE_BODY_POSITION, set_file_position
+from .util.retry import Retry
+from .util.ssl_match_hostname import CertificateError
+from .util.timeout import _DEFAULT_TIMEOUT, _TYPE_DEFAULT, Timeout
+from .util.url import Url, _encode_target
+from .util.url import _normalize_host as normalize_host
+from .util.url import parse_url
+from .util.util import to_str
+
+if typing.TYPE_CHECKING:
+    import ssl
+    from typing import Literal
+
+    from ._base_connection import BaseHTTPConnection, BaseHTTPSConnection
+
+log = logging.getLogger(__name__)
+
+_TYPE_TIMEOUT = typing.Union[Timeout, float, _TYPE_DEFAULT, None]
+
+_SelfT = typing.TypeVar("_SelfT")
+
+
+# Pool objects
+class ConnectionPool:
+    """
+    Base class for all connection pools, such as
+    :class:`.HTTPConnectionPool` and :class:`.HTTPSConnectionPool`.
+
+    .. note::
+       ConnectionPool.urlopen() does not normalize or percent-encode target URIs
+       which is useful if your target server doesn't support percent-encoded
+       target URIs.
+    """
+
+    scheme: str | None = None
+    QueueCls = queue.LifoQueue
+
+    def __init__(self, host: str, port: int | None = None) -> None:
+        if not host:
+            raise LocationValueError("No host specified.")
+
+        self.host = _normalize_host(host, scheme=self.scheme)
+        self.port = port
+
+        # This property uses 'normalize_host()' (not '_normalize_host()')
+        # to avoid removing square braces around IPv6 addresses.
+        # This value is sent to `HTTPConnection.set_tunnel()` if called
+        # because square braces are required for HTTP CONNECT tunneling.
+        self._tunnel_host = normalize_host(host, scheme=self.scheme).lower()
+
+    def __str__(self) -> str:
+        return f"{type(self).__name__}(host={self.host!r}, port={self.port!r})"
+
+    def __enter__(self: _SelfT) -> _SelfT:
+        return self
+
+    def __exit__(
+        self,
+        exc_type: type[BaseException] | None,
+        exc_val: BaseException | None,
+        exc_tb: TracebackType | None,
+    ) -> Literal[False]:
+        self.close()
+        # Return False to re-raise any potential exceptions
+        return False
+
+    def close(self) -> None:
+        """
+        Close all pooled connections and disable the pool.
+        """
+
+
+# This is taken from http://hg.python.org/cpython/file/7aaba721ebc0/Lib/socket.py#l252
+_blocking_errnos = {errno.EAGAIN, errno.EWOULDBLOCK}
+
+
+class HTTPConnectionPool(ConnectionPool, RequestMethods):
+    """
+    Thread-safe connection pool for one host.
+
+    :param host:
+        Host used for this HTTP Connection (e.g. "localhost"), passed into
+        :class:`http.client.HTTPConnection`.
+
+    :param port:
+        Port used for this HTTP Connection (None is equivalent to 80), passed
+        into :class:`http.client.HTTPConnection`.
+
+    :param timeout:
+        Socket timeout in seconds for each individual connection. This can
+        be a float or integer, which sets the timeout for the HTTP request,
+        or an instance of :class:`urllib3.util.Timeout` which gives you more
+        fine-grained control over request timeouts. After the constructor has
+        been parsed, this is always a `urllib3.util.Timeout` object.
+
+    :param maxsize:
+        Number of connections to save that can be reused. More than 1 is useful
+        in multithreaded situations. If ``block`` is set to False, more
+        connections will be created but they will not be saved once they've
+        been used.
+
+    :param block:
+        If set to True, no more than ``maxsize`` connections will be used at
+        a time. When no free connections are available, the call will block
+        until a connection has been released. This is a useful side effect for
+        particular multithreaded situations where one does not want to use more
+        than maxsize connections per host to prevent flooding.
+
+    :param headers:
+        Headers to include with all requests, unless other headers are given
+        explicitly.
+
+    :param retries:
+        Retry configuration to use by default with requests in this pool.
+
+    :param _proxy:
+        Parsed proxy URL, should not be used directly, instead, see
+        :class:`urllib3.ProxyManager`
+
+    :param _proxy_headers:
+        A dictionary with proxy headers, should not be used directly,
+        instead, see :class:`urllib3.ProxyManager`
+
+    :param \\**conn_kw:
+        Additional parameters are used to create fresh :class:`urllib3.connection.HTTPConnection`,
+        :class:`urllib3.connection.HTTPSConnection` instances.
+    """
+
+    scheme = "http"
+    ConnectionCls: (
+        type[BaseHTTPConnection] | type[BaseHTTPSConnection]
+    ) = HTTPConnection
+
+    def __init__(
+        self,
+        host: str,
+        port: int | None = None,
+        timeout: _TYPE_TIMEOUT | None = _DEFAULT_TIMEOUT,
+        maxsize: int = 1,
+        block: bool = False,
+        headers: typing.Mapping[str, str] | None = None,
+        retries: Retry | bool | int | None = None,
+        _proxy: Url | None = None,
+        _proxy_headers: typing.Mapping[str, str] | None = None,
+        _proxy_config: ProxyConfig | None = None,
+        **conn_kw: typing.Any,
+    ):
+        ConnectionPool.__init__(self, host, port)
+        RequestMethods.__init__(self, headers)
+
+        if not isinstance(timeout, Timeout):
+            timeout = Timeout.from_float(timeout)
+
+        if retries is None:
+            retries = Retry.DEFAULT
+
+        self.timeout = timeout
+        self.retries = retries
+
+        self.pool: queue.LifoQueue[typing.Any] | None = self.QueueCls(maxsize)
+        self.block = block
+
+        self.proxy = _proxy
+        self.proxy_headers = _proxy_headers or {}
+        self.proxy_config = _proxy_config
+
+        # Fill the queue up so that doing get() on it will block properly
+        for _ in range(maxsize):
+            self.pool.put(None)
+
+        # These are mostly for testing and debugging purposes.
+        self.num_connections = 0
+        self.num_requests = 0
+        self.conn_kw = conn_kw
+
+        if self.proxy:
+            # Enable Nagle's algorithm for proxies, to avoid packet fragmentation.
+            # We cannot know if the user has added default socket options, so we cannot replace the
+            # list.
+            self.conn_kw.setdefault("socket_options", [])
+
+            self.conn_kw["proxy"] = self.proxy
+            self.conn_kw["proxy_config"] = self.proxy_config
+
+        # Do not pass 'self' as callback to 'finalize'.
+        # Then the 'finalize' would keep an endless living (leak) to self.
+        # By just passing a reference to the pool allows the garbage collector
+        # to free self if nobody else has a reference to it.
+        pool = self.pool
+
+        # Close all the HTTPConnections in the pool before the
+        # HTTPConnectionPool object is garbage collected.
+        weakref.finalize(self, _close_pool_connections, pool)
+
+    def _new_conn(self) -> BaseHTTPConnection:
+        """
+        Return a fresh :class:`HTTPConnection`.
+        """
+        self.num_connections += 1
+        log.debug(
+            "Starting new HTTP connection (%d): %s:%s",
+            self.num_connections,
+            self.host,
+            self.port or "80",
+        )
+
+        conn = self.ConnectionCls(
+            host=self.host,
+            port=self.port,
+            timeout=self.timeout.connect_timeout,
+            **self.conn_kw,
+        )
+        return conn
+
+    def _get_conn(self, timeout: float | None = None) -> BaseHTTPConnection:
+        """
+        Get a connection. Will return a pooled connection if one is available.
+
+        If no connections are available and :prop:`.block` is ``False``, then a
+        fresh connection is returned.
+
+        :param timeout:
+            Seconds to wait before giving up and raising
+            :class:`urllib3.exceptions.EmptyPoolError` if the pool is empty and
+            :prop:`.block` is ``True``.
+        """
+        conn = None
+
+        if self.pool is None:
+            raise ClosedPoolError(self, "Pool is closed.")
+
+        try:
+            conn = self.pool.get(block=self.block, timeout=timeout)
+
+        except AttributeError:  # self.pool is None
+            raise ClosedPoolError(self, "Pool is closed.") from None  # Defensive:
+
+        except queue.Empty:
+            if self.block:
+                raise EmptyPoolError(
+                    self,
+                    "Pool is empty and a new connection can't be opened due to blocking mode.",
+                ) from None
+            pass  # Oh well, we'll create a new connection then
+
+        # If this is a persistent connection, check if it got disconnected
+        if conn and is_connection_dropped(conn):
+            log.debug("Resetting dropped connection: %s", self.host)
+            conn.close()
+
+        return conn or self._new_conn()
+
+    def _put_conn(self, conn: BaseHTTPConnection | None) -> None:
+        """
+        Put a connection back into the pool.
+
+        :param conn:
+            Connection object for the current host and port as returned by
+            :meth:`._new_conn` or :meth:`._get_conn`.
+
+        If the pool is already full, the connection is closed and discarded
+        because we exceeded maxsize. If connections are discarded frequently,
+        then maxsize should be increased.
+
+        If the pool is closed, then the connection will be closed and discarded.
+        """
+        if self.pool is not None:
+            try:
+                self.pool.put(conn, block=False)
+                return  # Everything is dandy, done.
+            except AttributeError:
+                # self.pool is None.
+                pass
+            except queue.Full:
+                # Connection never got put back into the pool, close it.
+                if conn:
+                    conn.close()
+
+                if self.block:
+                    # This should never happen if you got the conn from self._get_conn
+                    raise FullPoolError(
+                        self,
+                        "Pool reached maximum size and no more connections are allowed.",
+                    ) from None
+
+                log.warning(
+                    "Connection pool is full, discarding connection: %s. Connection pool size: %s",
+                    self.host,
+                    self.pool.qsize(),
+                )
+
+        # Connection never got put back into the pool, close it.
+        if conn:
+            conn.close()
+
+    def _validate_conn(self, conn: BaseHTTPConnection) -> None:
+        """
+        Called right before a request is made, after the socket is created.
+        """
+
+    def _prepare_proxy(self, conn: BaseHTTPConnection) -> None:
+        # Nothing to do for HTTP connections.
+        pass
+
+    def _get_timeout(self, timeout: _TYPE_TIMEOUT) -> Timeout:
+        """Helper that always returns a :class:`urllib3.util.Timeout`"""
+        if timeout is _DEFAULT_TIMEOUT:
+            return self.timeout.clone()
+
+        if isinstance(timeout, Timeout):
+            return timeout.clone()
+        else:
+            # User passed us an int/float. This is for backwards compatibility,
+            # can be removed later
+            return Timeout.from_float(timeout)
+
+    def _raise_timeout(
+        self,
+        err: BaseSSLError | OSError | SocketTimeout,
+        url: str,
+        timeout_value: _TYPE_TIMEOUT | None,
+    ) -> None:
+        """Is the error actually a timeout? Will raise a ReadTimeout or pass"""
+
+        if isinstance(err, SocketTimeout):
+            raise ReadTimeoutError(
+                self, url, f"Read timed out. (read timeout={timeout_value})"
+            ) from err
+
+        # See the above comment about EAGAIN in Python 3.
+        if hasattr(err, "errno") and err.errno in _blocking_errnos:
+            raise ReadTimeoutError(
+                self, url, f"Read timed out. (read timeout={timeout_value})"
+            ) from err
+
+    def _make_request(
+        self,
+        conn: BaseHTTPConnection,
+        method: str,
+        url: str,
+        body: _TYPE_BODY | None = None,
+        headers: typing.Mapping[str, str] | None = None,
+        retries: Retry | None = None,
+        timeout: _TYPE_TIMEOUT = _DEFAULT_TIMEOUT,
+        chunked: bool = False,
+        response_conn: BaseHTTPConnection | None = None,
+        preload_content: bool = True,
+        decode_content: bool = True,
+        enforce_content_length: bool = True,
+    ) -> BaseHTTPResponse:
+        """
+        Perform a request on a given urllib connection object taken from our
+        pool.
+
+        :param conn:
+            a connection from one of our connection pools
+
+        :param method:
+            HTTP request method (such as GET, POST, PUT, etc.)
+
+        :param url:
+            The URL to perform the request on.
+
+        :param body:
+            Data to send in the request body, either :class:`str`, :class:`bytes`,
+            an iterable of :class:`str`/:class:`bytes`, or a file-like object.
+
+        :param headers:
+            Dictionary of custom headers to send, such as User-Agent,
+            If-None-Match, etc. If None, pool headers are used. If provided,
+            these headers completely replace any pool-specific headers.
+
+        :param retries:
+            Configure the number of retries to allow before raising a
+            :class:`~urllib3.exceptions.MaxRetryError` exception.
+
+            Pass ``None`` to retry until you receive a response. Pass a
+            :class:`~urllib3.util.retry.Retry` object for fine-grained control
+            over different types of retries.
+            Pass an integer number to retry connection errors that many times,
+            but no other types of errors. Pass zero to never retry.
+
+            If ``False``, then retries are disabled and any exception is raised
+            immediately. Also, instead of raising a MaxRetryError on redirects,
+            the redirect response will be returned.
+
+        :type retries: :class:`~urllib3.util.retry.Retry`, False, or an int.
+
+        :param timeout:
+            If specified, overrides the default timeout for this one
+            request. It may be a float (in seconds) or an instance of
+            :class:`urllib3.util.Timeout`.
+
+        :param chunked:
+            If True, urllib3 will send the body using chunked transfer
+            encoding. Otherwise, urllib3 will send the body using the standard
+            content-length form. Defaults to False.
+
+        :param response_conn:
+            Set this to ``None`` if you will handle releasing the connection or
+            set the connection to have the response release it.
+
+        :param preload_content:
+          If True, the response's body will be preloaded during construction.
+
+        :param decode_content:
+            If True, will attempt to decode the body based on the
+            'content-encoding' header.
+
+        :param enforce_content_length:
+            Enforce content length checking. Body returned by server must match
+            value of Content-Length header, if present. Otherwise, raise error.
+        """
+        self.num_requests += 1
+
+        timeout_obj = self._get_timeout(timeout)
+        timeout_obj.start_connect()
+        conn.timeout = Timeout.resolve_default_timeout(timeout_obj.connect_timeout)
+
+        try:
+            # Trigger any extra validation we need to do.
+            try:
+                self._validate_conn(conn)
+            except (SocketTimeout, BaseSSLError) as e:
+                self._raise_timeout(err=e, url=url, timeout_value=conn.timeout)
+                raise
+
+        # _validate_conn() starts the connection to an HTTPS proxy
+        # so we need to wrap errors with 'ProxyError' here too.
+        except (
+            OSError,
+            NewConnectionError,
+            TimeoutError,
+            BaseSSLError,
+            CertificateError,
+            SSLError,
+        ) as e:
+            new_e: Exception = e
+            if isinstance(e, (BaseSSLError, CertificateError)):
+                new_e = SSLError(e)
+            # If the connection didn't successfully connect to it's proxy
+            # then there
+            if isinstance(
+                new_e, (OSError, NewConnectionError, TimeoutError, SSLError)
+            ) and (conn and conn.proxy and not conn.has_connected_to_proxy):
+                new_e = _wrap_proxy_error(new_e, conn.proxy.scheme)
+            raise new_e
+
+        # conn.request() calls http.client.*.request, not the method in
+        # urllib3.request. It also calls makefile (recv) on the socket.
+        try:
+            conn.request(
+                method,
+                url,
+                body=body,
+                headers=headers,
+                chunked=chunked,
+                preload_content=preload_content,
+                decode_content=decode_content,
+                enforce_content_length=enforce_content_length,
+            )
+
+        # We are swallowing BrokenPipeError (errno.EPIPE) since the server is
+        # legitimately able to close the connection after sending a valid response.
+        # With this behaviour, the received response is still readable.
+        except BrokenPipeError:
+            pass
+        except OSError as e:
+            # MacOS/Linux
+            # EPROTOTYPE and ECONNRESET are needed on macOS
+            # https://erickt.github.io/blog/2014/11/19/adventures-in-debugging-a-potential-osx-kernel-bug/
+            # Condition changed later to emit ECONNRESET instead of only EPROTOTYPE.
+            if e.errno != errno.EPROTOTYPE and e.errno != errno.ECONNRESET:
+                raise
+
+        # Reset the timeout for the recv() on the socket
+        read_timeout = timeout_obj.read_timeout
+
+        if not conn.is_closed:
+            # In Python 3 socket.py will catch EAGAIN and return None when you
+            # try and read into the file pointer created by http.client, which
+            # instead raises a BadStatusLine exception. Instead of catching
+            # the exception and assuming all BadStatusLine exceptions are read
+            # timeouts, check for a zero timeout before making the request.
+            if read_timeout == 0:
+                raise ReadTimeoutError(
+                    self, url, f"Read timed out. (read timeout={read_timeout})"
+                )
+            conn.timeout = read_timeout
+
+        # Receive the response from the server
+        try:
+            response = conn.getresponse()
+        except (BaseSSLError, OSError) as e:
+            self._raise_timeout(err=e, url=url, timeout_value=read_timeout)
+            raise
+
+        # Set properties that are used by the pooling layer.
+        response.retries = retries
+        response._connection = response_conn  # type: ignore[attr-defined]
+        response._pool = self  # type: ignore[attr-defined]
+
+        # emscripten connection doesn't have _http_vsn_str
+        http_version = getattr(conn, "_http_vsn_str", "HTTP/?")
+        log.debug(
+            '%s://%s:%s "%s %s %s" %s %s',
+            self.scheme,
+            self.host,
+            self.port,
+            method,
+            url,
+            # HTTP version
+            http_version,
+            response.status,
+            response.length_remaining,
+        )
+
+        return response
+
+    def close(self) -> None:
+        """
+        Close all pooled connections and disable the pool.
+        """
+        if self.pool is None:
+            return
+        # Disable access to the pool
+        old_pool, self.pool = self.pool, None
+
+        # Close all the HTTPConnections in the pool.
+        _close_pool_connections(old_pool)
+
+    def is_same_host(self, url: str) -> bool:
+        """
+        Check if the given ``url`` is a member of the same host as this
+        connection pool.
+        """
+        if url.startswith("/"):
+            return True
+
+        # TODO: Add optional support for socket.gethostbyname checking.
+        scheme, _, host, port, *_ = parse_url(url)
+        scheme = scheme or "http"
+        if host is not None:
+            host = _normalize_host(host, scheme=scheme)
+
+        # Use explicit default port for comparison when none is given
+        if self.port and not port:
+            port = port_by_scheme.get(scheme)
+        elif not self.port and port == port_by_scheme.get(scheme):
+            port = None
+
+        return (scheme, host, port) == (self.scheme, self.host, self.port)
+
+    def urlopen(  # type: ignore[override]
+        self,
+        method: str,
+        url: str,
+        body: _TYPE_BODY | None = None,
+        headers: typing.Mapping[str, str] | None = None,
+        retries: Retry | bool | int | None = None,
+        redirect: bool = True,
+        assert_same_host: bool = True,
+        timeout: _TYPE_TIMEOUT = _DEFAULT_TIMEOUT,
+        pool_timeout: int | None = None,
+        release_conn: bool | None = None,
+        chunked: bool = False,
+        body_pos: _TYPE_BODY_POSITION | None = None,
+        preload_content: bool = True,
+        decode_content: bool = True,
+        **response_kw: typing.Any,
+    ) -> BaseHTTPResponse:
+        """
+        Get a connection from the pool and perform an HTTP request. This is the
+        lowest level call for making a request, so you'll need to specify all
+        the raw details.
+
+        .. note::
+
+           More commonly, it's appropriate to use a convenience method
+           such as :meth:`request`.
+
+        .. note::
+
+           `release_conn` will only behave as expected if
+           `preload_content=False` because we want to make
+           `preload_content=False` the default behaviour someday soon without
+           breaking backwards compatibility.
+
+        :param method:
+            HTTP request method (such as GET, POST, PUT, etc.)
+
+        :param url:
+            The URL to perform the request on.
+
+        :param body:
+            Data to send in the request body, either :class:`str`, :class:`bytes`,
+            an iterable of :class:`str`/:class:`bytes`, or a file-like object.
+
+        :param headers:
+            Dictionary of custom headers to send, such as User-Agent,
+            If-None-Match, etc. If None, pool headers are used. If provided,
+            these headers completely replace any pool-specific headers.
+
+        :param retries:
+            Configure the number of retries to allow before raising a
+            :class:`~urllib3.exceptions.MaxRetryError` exception.
+
+            If ``None`` (default) will retry 3 times, see ``Retry.DEFAULT``. Pass a
+            :class:`~urllib3.util.retry.Retry` object for fine-grained control
+            over different types of retries.
+            Pass an integer number to retry connection errors that many times,
+            but no other types of errors. Pass zero to never retry.
+
+            If ``False``, then retries are disabled and any exception is raised
+            immediately. Also, instead of raising a MaxRetryError on redirects,
+            the redirect response will be returned.
+
+        :type retries: :class:`~urllib3.util.retry.Retry`, False, or an int.
+
+        :param redirect:
+            If True, automatically handle redirects (status codes 301, 302,
+            303, 307, 308). Each redirect counts as a retry. Disabling retries
+            will disable redirect, too.
+
+        :param assert_same_host:
+            If ``True``, will make sure that the host of the pool requests is
+            consistent else will raise HostChangedError. When ``False``, you can
+            use the pool on an HTTP proxy and request foreign hosts.
+
+        :param timeout:
+            If specified, overrides the default timeout for this one
+            request. It may be a float (in seconds) or an instance of
+            :class:`urllib3.util.Timeout`.
+
+        :param pool_timeout:
+            If set and the pool is set to block=True, then this method will
+            block for ``pool_timeout`` seconds and raise EmptyPoolError if no
+            connection is available within the time period.
+
+        :param bool preload_content:
+            If True, the response's body will be preloaded into memory.
+
+        :param bool decode_content:
+            If True, will attempt to decode the body based on the
+            'content-encoding' header.
+
+        :param release_conn:
+            If False, then the urlopen call will not release the connection
+            back into the pool once a response is received (but will release if
+            you read the entire contents of the response such as when
+            `preload_content=True`). This is useful if you're not preloading
+            the response's content immediately. You will need to call
+            ``r.release_conn()`` on the response ``r`` to return the connection
+            back into the pool. If None, it takes the value of ``preload_content``
+            which defaults to ``True``.
+
+        :param bool chunked:
+            If True, urllib3 will send the body using chunked transfer
+            encoding. Otherwise, urllib3 will send the body using the standard
+            content-length form. Defaults to False.
+
+        :param int body_pos:
+            Position to seek to in file-like body in the event of a retry or
+            redirect. Typically this won't need to be set because urllib3 will
+            auto-populate the value when needed.
+        """
+        parsed_url = parse_url(url)
+        destination_scheme = parsed_url.scheme
+
+        if headers is None:
+            headers = self.headers
+
+        if not isinstance(retries, Retry):
+            retries = Retry.from_int(retries, redirect=redirect, default=self.retries)
+
+        if release_conn is None:
+            release_conn = preload_content
+
+        # Check host
+        if assert_same_host and not self.is_same_host(url):
+            raise HostChangedError(self, url, retries)
+
+        # Ensure that the URL we're connecting to is properly encoded
+        if url.startswith("/"):
+            url = to_str(_encode_target(url))
+        else:
+            url = to_str(parsed_url.url)
+
+        conn = None
+
+        # Track whether `conn` needs to be released before
+        # returning/raising/recursing. Update this variable if necessary, and
+        # leave `release_conn` constant throughout the function. That way, if
+        # the function recurses, the original value of `release_conn` will be
+        # passed down into the recursive call, and its value will be respected.
+        #
+        # See issue #651 [1] for details.
+        #
+        # [1] <https://github.com/urllib3/urllib3/issues/651>
+        release_this_conn = release_conn
+
+        http_tunnel_required = connection_requires_http_tunnel(
+            self.proxy, self.proxy_config, destination_scheme
+        )
+
+        # Merge the proxy headers. Only done when not using HTTP CONNECT. We
+        # have to copy the headers dict so we can safely change it without those
+        # changes being reflected in anyone else's copy.
+        if not http_tunnel_required:
+            headers = headers.copy()  # type: ignore[attr-defined]
+            headers.update(self.proxy_headers)  # type: ignore[union-attr]
+
+        # Must keep the exception bound to a separate variable or else Python 3
+        # complains about UnboundLocalError.
+        err = None
+
+        # Keep track of whether we cleanly exited the except block. This
+        # ensures we do proper cleanup in finally.
+        clean_exit = False
+
+        # Rewind body position, if needed. Record current position
+        # for future rewinds in the event of a redirect/retry.
+        body_pos = set_file_position(body, body_pos)
+
+        try:
+            # Request a connection from the queue.
+            timeout_obj = self._get_timeout(timeout)
+            conn = self._get_conn(timeout=pool_timeout)
+
+            conn.timeout = timeout_obj.connect_timeout  # type: ignore[assignment]
+
+            # Is this a closed/new connection that requires CONNECT tunnelling?
+            if self.proxy is not None and http_tunnel_required and conn.is_closed:
+                try:
+                    self._prepare_proxy(conn)
+                except (BaseSSLError, OSError, SocketTimeout) as e:
+                    self._raise_timeout(
+                        err=e, url=self.proxy.url, timeout_value=conn.timeout
+                    )
+                    raise
+
+            # If we're going to release the connection in ``finally:``, then
+            # the response doesn't need to know about the connection. Otherwise
+            # it will also try to release it and we'll have a double-release
+            # mess.
+            response_conn = conn if not release_conn else None
+
+            # Make the request on the HTTPConnection object
+            response = self._make_request(
+                conn,
+                method,
+                url,
+                timeout=timeout_obj,
+                body=body,
+                headers=headers,
+                chunked=chunked,
+                retries=retries,
+                response_conn=response_conn,
+                preload_content=preload_content,
+                decode_content=decode_content,
+                **response_kw,
+            )
+
+            # Everything went great!
+            clean_exit = True
+
+        except EmptyPoolError:
+            # Didn't get a connection from the pool, no need to clean up
+            clean_exit = True
+            release_this_conn = False
+            raise
+
+        except (
+            TimeoutError,
+            HTTPException,
+            OSError,
+            ProtocolError,
+            BaseSSLError,
+            SSLError,
+            CertificateError,
+            ProxyError,
+        ) as e:
+            # Discard the connection for these exceptions. It will be
+            # replaced during the next _get_conn() call.
+            clean_exit = False
+            new_e: Exception = e
+            if isinstance(e, (BaseSSLError, CertificateError)):
+                new_e = SSLError(e)
+            if isinstance(
+                new_e,
+                (
+                    OSError,
+                    NewConnectionError,
+                    TimeoutError,
+                    SSLError,
+                    HTTPException,
+                ),
+            ) and (conn and conn.proxy and not conn.has_connected_to_proxy):
+                new_e = _wrap_proxy_error(new_e, conn.proxy.scheme)
+            elif isinstance(new_e, (OSError, HTTPException)):
+                new_e = ProtocolError("Connection aborted.", new_e)
+
+            retries = retries.increment(
+                method, url, error=new_e, _pool=self, _stacktrace=sys.exc_info()[2]
+            )
+            retries.sleep()
+
+            # Keep track of the error for the retry warning.
+            err = e
+
+        finally:
+            if not clean_exit:
+                # We hit some kind of exception, handled or otherwise. We need
+                # to throw the connection away unless explicitly told not to.
+                # Close the connection, set the variable to None, and make sure
+                # we put the None back in the pool to avoid leaking it.
+                if conn:
+                    conn.close()
+                    conn = None
+                release_this_conn = True
+
+            if release_this_conn:
+                # Put the connection back to be reused. If the connection is
+                # expired then it will be None, which will get replaced with a
+                # fresh connection during _get_conn.
+                self._put_conn(conn)
+
+        if not conn:
+            # Try again
+            log.warning(
+                "Retrying (%r) after connection broken by '%r': %s", retries, err, url
+            )
+            return self.urlopen(
+                method,
+                url,
+                body,
+                headers,
+                retries,
+                redirect,
+                assert_same_host,
+                timeout=timeout,
+                pool_timeout=pool_timeout,
+                release_conn=release_conn,
+                chunked=chunked,
+                body_pos=body_pos,
+                preload_content=preload_content,
+                decode_content=decode_content,
+                **response_kw,
+            )
+
+        # Handle redirect?
+        redirect_location = redirect and response.get_redirect_location()
+        if redirect_location:
+            if response.status == 303:
+                # Change the method according to RFC 9110, Section 15.4.4.
+                method = "GET"
+                # And lose the body not to transfer anything sensitive.
+                body = None
+                headers = HTTPHeaderDict(headers)._prepare_for_method_change()
+
+            try:
+                retries = retries.increment(method, url, response=response, _pool=self)
+            except MaxRetryError:
+                if retries.raise_on_redirect:
+                    response.drain_conn()
+                    raise
+                return response
+
+            response.drain_conn()
+            retries.sleep_for_retry(response)
+            log.debug("Redirecting %s -> %s", url, redirect_location)
+            return self.urlopen(
+                method,
+                redirect_location,
+                body,
+                headers,
+                retries=retries,
+                redirect=redirect,
+                assert_same_host=assert_same_host,
+                timeout=timeout,
+                pool_timeout=pool_timeout,
+                release_conn=release_conn,
+                chunked=chunked,
+                body_pos=body_pos,
+                preload_content=preload_content,
+                decode_content=decode_content,
+                **response_kw,
+            )
+
+        # Check if we should retry the HTTP response.
+        has_retry_after = bool(response.headers.get("Retry-After"))
+        if retries.is_retry(method, response.status, has_retry_after):
+            try:
+                retries = retries.increment(method, url, response=response, _pool=self)
+            except MaxRetryError:
+                if retries.raise_on_status:
+                    response.drain_conn()
+                    raise
+                return response
+
+            response.drain_conn()
+            retries.sleep(response)
+            log.debug("Retry: %s", url)
+            return self.urlopen(
+                method,
+                url,
+                body,
+                headers,
+                retries=retries,
+                redirect=redirect,
+                assert_same_host=assert_same_host,
+                timeout=timeout,
+                pool_timeout=pool_timeout,
+                release_conn=release_conn,
+                chunked=chunked,
+                body_pos=body_pos,
+                preload_content=preload_content,
+                decode_content=decode_content,
+                **response_kw,
+            )
+
+        return response
+
+
+class HTTPSConnectionPool(HTTPConnectionPool):
+    """
+    Same as :class:`.HTTPConnectionPool`, but HTTPS.
+
+    :class:`.HTTPSConnection` uses one of ``assert_fingerprint``,
+    ``assert_hostname`` and ``host`` in this order to verify connections.
+    If ``assert_hostname`` is False, no verification is done.
+
+    The ``key_file``, ``cert_file``, ``cert_reqs``, ``ca_certs``,
+    ``ca_cert_dir``, ``ssl_version``, ``key_password`` are only used if :mod:`ssl`
+    is available and are fed into :meth:`urllib3.util.ssl_wrap_socket` to upgrade
+    the connection socket into an SSL socket.
+    """
+
+    scheme = "https"
+    ConnectionCls: type[BaseHTTPSConnection] = HTTPSConnection
+
+    def __init__(
+        self,
+        host: str,
+        port: int | None = None,
+        timeout: _TYPE_TIMEOUT | None = _DEFAULT_TIMEOUT,
+        maxsize: int = 1,
+        block: bool = False,
+        headers: typing.Mapping[str, str] | None = None,
+        retries: Retry | bool | int | None = None,
+        _proxy: Url | None = None,
+        _proxy_headers: typing.Mapping[str, str] | None = None,
+        key_file: str | None = None,
+        cert_file: str | None = None,
+        cert_reqs: int | str | None = None,
+        key_password: str | None = None,
+        ca_certs: str | None = None,
+        ssl_version: int | str | None = None,
+        ssl_minimum_version: ssl.TLSVersion | None = None,
+        ssl_maximum_version: ssl.TLSVersion | None = None,
+        assert_hostname: str | Literal[False] | None = None,
+        assert_fingerprint: str | None = None,
+        ca_cert_dir: str | None = None,
+        **conn_kw: typing.Any,
+    ) -> None:
+        super().__init__(
+            host,
+            port,
+            timeout,
+            maxsize,
+            block,
+            headers,
+            retries,
+            _proxy,
+            _proxy_headers,
+            **conn_kw,
+        )
+
+        self.key_file = key_file
+        self.cert_file = cert_file
+        self.cert_reqs = cert_reqs
+        self.key_password = key_password
+        self.ca_certs = ca_certs
+        self.ca_cert_dir = ca_cert_dir
+        self.ssl_version = ssl_version
+        self.ssl_minimum_version = ssl_minimum_version
+        self.ssl_maximum_version = ssl_maximum_version
+        self.assert_hostname = assert_hostname
+        self.assert_fingerprint = assert_fingerprint
+
+    def _prepare_proxy(self, conn: HTTPSConnection) -> None:  # type: ignore[override]
+        """Establishes a tunnel connection through HTTP CONNECT."""
+        if self.proxy and self.proxy.scheme == "https":
+            tunnel_scheme = "https"
+        else:
+            tunnel_scheme = "http"
+
+        conn.set_tunnel(
+            scheme=tunnel_scheme,
+            host=self._tunnel_host,
+            port=self.port,
+            headers=self.proxy_headers,
+        )
+        conn.connect()
+
+    def _new_conn(self) -> BaseHTTPSConnection:
+        """
+        Return a fresh :class:`urllib3.connection.HTTPConnection`.
+        """
+        self.num_connections += 1
+        log.debug(
+            "Starting new HTTPS connection (%d): %s:%s",
+            self.num_connections,
+            self.host,
+            self.port or "443",
+        )
+
+        if not self.ConnectionCls or self.ConnectionCls is DummyConnection:  # type: ignore[comparison-overlap]
+            raise ImportError(
+                "Can't connect to HTTPS URL because the SSL module is not available."
+            )
+
+        actual_host: str = self.host
+        actual_port = self.port
+        if self.proxy is not None and self.proxy.host is not None:
+            actual_host = self.proxy.host
+            actual_port = self.proxy.port
+
+        return self.ConnectionCls(
+            host=actual_host,
+            port=actual_port,
+            timeout=self.timeout.connect_timeout,
+            cert_file=self.cert_file,
+            key_file=self.key_file,
+            key_password=self.key_password,
+            cert_reqs=self.cert_reqs,
+            ca_certs=self.ca_certs,
+            ca_cert_dir=self.ca_cert_dir,
+            assert_hostname=self.assert_hostname,
+            assert_fingerprint=self.assert_fingerprint,
+            ssl_version=self.ssl_version,
+            ssl_minimum_version=self.ssl_minimum_version,
+            ssl_maximum_version=self.ssl_maximum_version,
+            **self.conn_kw,
+        )
+
+    def _validate_conn(self, conn: BaseHTTPConnection) -> None:
+        """
+        Called right before a request is made, after the socket is created.
+        """
+        super()._validate_conn(conn)
+
+        # Force connect early to allow us to validate the connection.
+        if conn.is_closed:
+            conn.connect()
+
+        # TODO revise this, see https://github.com/urllib3/urllib3/issues/2791
+        if not conn.is_verified and not conn.proxy_is_verified:
+            warnings.warn(
+                (
+                    f"Unverified HTTPS request is being made to host '{conn.host}'. "
+                    "Adding certificate verification is strongly advised. See: "
+                    "https://urllib3.readthedocs.io/en/latest/advanced-usage.html"
+                    "#tls-warnings"
+                ),
+                InsecureRequestWarning,
+            )
+
+
+def connection_from_url(url: str, **kw: typing.Any) -> HTTPConnectionPool:
+    """
+    Given a url, return an :class:`.ConnectionPool` instance of its host.
+
+    This is a shortcut for not having to parse out the scheme, host, and port
+    of the url before creating an :class:`.ConnectionPool` instance.
+
+    :param url:
+        Absolute URL string that must include the scheme. Port is optional.
+
+    :param \\**kw:
+        Passes additional parameters to the constructor of the appropriate
+        :class:`.ConnectionPool`. Useful for specifying things like
+        timeout, maxsize, headers, etc.
+
+    Example::
+
+        >>> conn = connection_from_url('http://google.com/')
+        >>> r = conn.request('GET', '/')
+    """
+    scheme, _, host, port, *_ = parse_url(url)
+    scheme = scheme or "http"
+    port = port or port_by_scheme.get(scheme, 80)
+    if scheme == "https":
+        return HTTPSConnectionPool(host, port=port, **kw)  # type: ignore[arg-type]
+    else:
+        return HTTPConnectionPool(host, port=port, **kw)  # type: ignore[arg-type]
+
+
+@typing.overload
+def _normalize_host(host: None, scheme: str | None) -> None:
+    ...
+
+
+@typing.overload
+def _normalize_host(host: str, scheme: str | None) -> str:
+    ...
+
+
+def _normalize_host(host: str | None, scheme: str | None) -> str | None:
+    """
+    Normalize hosts for comparisons and use with sockets.
+    """
+
+    host = normalize_host(host, scheme)
+
+    # httplib doesn't like it when we include brackets in IPv6 addresses
+    # Specifically, if we include brackets but also pass the port then
+    # httplib crazily doubles up the square brackets on the Host header.
+    # Instead, we need to make sure we never pass ``None`` as the port.
+    # However, for backward compatibility reasons we can't actually
+    # *assert* that.  See http://bugs.python.org/issue28539
+    if host and host.startswith("[") and host.endswith("]"):
+        host = host[1:-1]
+    return host
+
+
+def _url_from_pool(
+    pool: HTTPConnectionPool | HTTPSConnectionPool, path: str | None = None
+) -> str:
+    """Returns the URL from a given connection pool. This is mainly used for testing and logging."""
+    return Url(scheme=pool.scheme, host=pool.host, port=pool.port, path=path).url
+
+
+def _close_pool_connections(pool: queue.LifoQueue[typing.Any]) -> None:
+    """Drains a queue of connections and closes each one."""
+    try:
+        while True:
+            conn = pool.get(block=False)
+            if conn:
+                conn.close()
+    except queue.Empty:
+        pass  # Done.

venv/lib/python3.10/site-packages/urllib3/exceptions.py

@@ -0,0 +1,321 @@
+from __future__ import annotations
+
+import socket
+import typing
+import warnings
+from email.errors import MessageDefect
+from http.client import IncompleteRead as httplib_IncompleteRead
+
+if typing.TYPE_CHECKING:
+    from .connection import HTTPConnection
+    from .connectionpool import ConnectionPool
+    from .response import HTTPResponse
+    from .util.retry import Retry
+
+# Base Exceptions
+
+
+class HTTPError(Exception):
+    """Base exception used by this module."""
+
+
+class HTTPWarning(Warning):
+    """Base warning used by this module."""
+
+
+_TYPE_REDUCE_RESULT = typing.Tuple[
+    typing.Callable[..., object], typing.Tuple[object, ...]
+]
+
+
+class PoolError(HTTPError):
+    """Base exception for errors caused within a pool."""
+
+    def __init__(self, pool: ConnectionPool, message: str) -> None:
+        self.pool = pool
+        super().__init__(f"{pool}: {message}")
+
+    def __reduce__(self) -> _TYPE_REDUCE_RESULT:
+        # For pickling purposes.
+        return self.__class__, (None, None)
+
+
+class RequestError(PoolError):
+    """Base exception for PoolErrors that have associated URLs."""
+
+    def __init__(self, pool: ConnectionPool, url: str, message: str) -> None:
+        self.url = url
+        super().__init__(pool, message)
+
+    def __reduce__(self) -> _TYPE_REDUCE_RESULT:
+        # For pickling purposes.
+        return self.__class__, (None, self.url, None)
+
+
+class SSLError(HTTPError):
+    """Raised when SSL certificate fails in an HTTPS connection."""
+
+
+class ProxyError(HTTPError):
+    """Raised when the connection to a proxy fails."""
+
+    # The original error is also available as __cause__.
+    original_error: Exception
+
+    def __init__(self, message: str, error: Exception) -> None:
+        super().__init__(message, error)
+        self.original_error = error
+
+
+class DecodeError(HTTPError):
+    """Raised when automatic decoding based on Content-Type fails."""
+
+
+class ProtocolError(HTTPError):
+    """Raised when something unexpected happens mid-request/response."""
+
+
+#: Renamed to ProtocolError but aliased for backwards compatibility.
+ConnectionError = ProtocolError
+
+
+# Leaf Exceptions
+
+
+class MaxRetryError(RequestError):
+    """Raised when the maximum number of retries is exceeded.
+
+    :param pool: The connection pool
+    :type pool: :class:`~urllib3.connectionpool.HTTPConnectionPool`
+    :param str url: The requested Url
+    :param reason: The underlying error
+    :type reason: :class:`Exception`
+
+    """
+
+    def __init__(
+        self, pool: ConnectionPool, url: str, reason: Exception | None = None
+    ) -> None:
+        self.reason = reason
+
+        message = f"Max retries exceeded with url: {url} (Caused by {reason!r})"
+
+        super().__init__(pool, url, message)
+
+
+class HostChangedError(RequestError):
+    """Raised when an existing pool gets a request for a foreign host."""
+
+    def __init__(
+        self, pool: ConnectionPool, url: str, retries: Retry | int = 3
+    ) -> None:
+        message = f"Tried to open a foreign host with url: {url}"
+        super().__init__(pool, url, message)
+        self.retries = retries
+
+
+class TimeoutStateError(HTTPError):
+    """Raised when passing an invalid state to a timeout"""
+
+
+class TimeoutError(HTTPError):
+    """Raised when a socket timeout error occurs.
+
+    Catching this error will catch both :exc:`ReadTimeoutErrors
+    <ReadTimeoutError>` and :exc:`ConnectTimeoutErrors <ConnectTimeoutError>`.
+    """
+
+
+class ReadTimeoutError(TimeoutError, RequestError):
+    """Raised when a socket timeout occurs while receiving data from a server"""
+
+
+# This timeout error does not have a URL attached and needs to inherit from the
+# base HTTPError
+class ConnectTimeoutError(TimeoutError):
+    """Raised when a socket timeout occurs while connecting to a server"""
+
+
+class NewConnectionError(ConnectTimeoutError, HTTPError):
+    """Raised when we fail to establish a new connection. Usually ECONNREFUSED."""
+
+    def __init__(self, conn: HTTPConnection, message: str) -> None:
+        self.conn = conn
+        super().__init__(f"{conn}: {message}")
+
+    @property
+    def pool(self) -> HTTPConnection:
+        warnings.warn(
+            "The 'pool' property is deprecated and will be removed "
+            "in urllib3 v2.1.0. Use 'conn' instead.",
+            DeprecationWarning,
+            stacklevel=2,
+        )
+
+        return self.conn
+
+
+class NameResolutionError(NewConnectionError):
+    """Raised when host name resolution fails."""
+
+    def __init__(self, host: str, conn: HTTPConnection, reason: socket.gaierror):
+        message = f"Failed to resolve '{host}' ({reason})"
+        super().__init__(conn, message)
+
+
+class EmptyPoolError(PoolError):
+    """Raised when a pool runs out of connections and no more are allowed."""
+
+
+class FullPoolError(PoolError):
+    """Raised when we try to add a connection to a full pool in blocking mode."""
+
+
+class ClosedPoolError(PoolError):
+    """Raised when a request enters a pool after the pool has been closed."""
+
+
+class LocationValueError(ValueError, HTTPError):
+    """Raised when there is something wrong with a given URL input."""
+
+
+class LocationParseError(LocationValueError):
+    """Raised when get_host or similar fails to parse the URL input."""
+
+    def __init__(self, location: str) -> None:
+        message = f"Failed to parse: {location}"
+        super().__init__(message)
+
+        self.location = location
+
+
+class URLSchemeUnknown(LocationValueError):
+    """Raised when a URL input has an unsupported scheme."""
+
+    def __init__(self, scheme: str):
+        message = f"Not supported URL scheme {scheme}"
+        super().__init__(message)
+
+        self.scheme = scheme
+
+
+class ResponseError(HTTPError):
+    """Used as a container for an error reason supplied in a MaxRetryError."""
+
+    GENERIC_ERROR = "too many error responses"
+    SPECIFIC_ERROR = "too many {status_code} error responses"
+
+
+class SecurityWarning(HTTPWarning):
+    """Warned when performing security reducing actions"""
+
+
+class InsecureRequestWarning(SecurityWarning):
+    """Warned when making an unverified HTTPS request."""
+
+
+class NotOpenSSLWarning(SecurityWarning):
+    """Warned when using unsupported SSL library"""
+
+
+class SystemTimeWarning(SecurityWarning):
+    """Warned when system time is suspected to be wrong"""
+
+
+class InsecurePlatformWarning(SecurityWarning):
+    """Warned when certain TLS/SSL configuration is not available on a platform."""
+
+
+class DependencyWarning(HTTPWarning):
+    """
+    Warned when an attempt is made to import a module with missing optional
+    dependencies.
+    """
+
+
+class ResponseNotChunked(ProtocolError, ValueError):
+    """Response needs to be chunked in order to read it as chunks."""
+
+
+class BodyNotHttplibCompatible(HTTPError):
+    """
+    Body should be :class:`http.client.HTTPResponse` like
+    (have an fp attribute which returns raw chunks) for read_chunked().
+    """
+
+
+class IncompleteRead(HTTPError, httplib_IncompleteRead):
+    """
+    Response length doesn't match expected Content-Length
+
+    Subclass of :class:`http.client.IncompleteRead` to allow int value
+    for ``partial`` to avoid creating large objects on streamed reads.
+    """
+
+    partial: int  # type: ignore[assignment]
+    expected: int
+
+    def __init__(self, partial: int, expected: int) -> None:
+        self.partial = partial
+        self.expected = expected
+
+    def __repr__(self) -> str:
+        return "IncompleteRead(%i bytes read, %i more expected)" % (
+            self.partial,
+            self.expected,
+        )
+
+
+class InvalidChunkLength(HTTPError, httplib_IncompleteRead):
+    """Invalid chunk length in a chunked response."""
+
+    def __init__(self, response: HTTPResponse, length: bytes) -> None:
+        self.partial: int = response.tell()  # type: ignore[assignment]
+        self.expected: int | None = response.length_remaining
+        self.response = response
+        self.length = length
+
+    def __repr__(self) -> str:
+        return "InvalidChunkLength(got length %r, %i bytes read)" % (
+            self.length,
+            self.partial,
+        )
+
+
+class InvalidHeader(HTTPError):
+    """The header provided was somehow invalid."""
+
+
+class ProxySchemeUnknown(AssertionError, URLSchemeUnknown):
+    """ProxyManager does not support the supplied scheme"""
+
+    # TODO(t-8ch): Stop inheriting from AssertionError in v2.0.
+
+    def __init__(self, scheme: str | None) -> None:
+        # 'localhost' is here because our URL parser parses
+        # localhost:8080 -> scheme=localhost, remove if we fix this.
+        if scheme == "localhost":
+            scheme = None
+        if scheme is None:
+            message = "Proxy URL had no scheme, should start with http:// or https://"
+        else:
+            message = f"Proxy URL had unsupported scheme {scheme}, should use http:// or https://"
+        super().__init__(message)
+
+
+class ProxySchemeUnsupported(ValueError):
+    """Fetching HTTPS resources through HTTPS proxies is unsupported"""
+
+
+class HeaderParsingError(HTTPError):
+    """Raised by assert_header_parsing, but we convert it to a log.warning statement."""
+
+    def __init__(
+        self, defects: list[MessageDefect], unparsed_data: bytes | str | None
+    ) -> None:
+        message = f"{defects or 'Unknown'}, unparsed data: {unparsed_data!r}"
+        super().__init__(message)
+
+
+class UnrewindableBodyError(HTTPError):
+    """urllib3 encountered an error when trying to rewind a body"""

venv/lib/python3.10/site-packages/urllib3/fields.py

@@ -0,0 +1,341 @@
+from __future__ import annotations
+
+import email.utils
+import mimetypes
+import typing
+
+_TYPE_FIELD_VALUE = typing.Union[str, bytes]
+_TYPE_FIELD_VALUE_TUPLE = typing.Union[
+    _TYPE_FIELD_VALUE,
+    typing.Tuple[str, _TYPE_FIELD_VALUE],
+    typing.Tuple[str, _TYPE_FIELD_VALUE, str],
+]
+
+
+def guess_content_type(
+    filename: str | None, default: str = "application/octet-stream"
+) -> str:
+    """
+    Guess the "Content-Type" of a file.
+
+    :param filename:
+        The filename to guess the "Content-Type" of using :mod:`mimetypes`.
+    :param default:
+        If no "Content-Type" can be guessed, default to `default`.
+    """
+    if filename:
+        return mimetypes.guess_type(filename)[0] or default
+    return default
+
+
+def format_header_param_rfc2231(name: str, value: _TYPE_FIELD_VALUE) -> str:
+    """
+    Helper function to format and quote a single header parameter using the
+    strategy defined in RFC 2231.
+
+    Particularly useful for header parameters which might contain
+    non-ASCII values, like file names. This follows
+    `RFC 2388 Section 4.4 <https://tools.ietf.org/html/rfc2388#section-4.4>`_.
+
+    :param name:
+        The name of the parameter, a string expected to be ASCII only.
+    :param value:
+        The value of the parameter, provided as ``bytes`` or `str``.
+    :returns:
+        An RFC-2231-formatted unicode string.
+
+    .. deprecated:: 2.0.0
+        Will be removed in urllib3 v2.1.0. This is not valid for
+        ``multipart/form-data`` header parameters.
+    """
+    import warnings
+
+    warnings.warn(
+        "'format_header_param_rfc2231' is deprecated and will be "
+        "removed in urllib3 v2.1.0. This is not valid for "
+        "multipart/form-data header parameters.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
+
+    if isinstance(value, bytes):
+        value = value.decode("utf-8")
+
+    if not any(ch in value for ch in '"\\\r\n'):
+        result = f'{name}="{value}"'
+        try:
+            result.encode("ascii")
+        except (UnicodeEncodeError, UnicodeDecodeError):
+            pass
+        else:
+            return result
+
+    value = email.utils.encode_rfc2231(value, "utf-8")
+    value = f"{name}*={value}"
+
+    return value
+
+
+def format_multipart_header_param(name: str, value: _TYPE_FIELD_VALUE) -> str:
+    """
+    Format and quote a single multipart header parameter.
+
+    This follows the `WHATWG HTML Standard`_ as of 2021/06/10, matching
+    the behavior of current browser and curl versions. Values are
+    assumed to be UTF-8. The ``\\n``, ``\\r``, and ``"`` characters are
+    percent encoded.
+
+    .. _WHATWG HTML Standard:
+        https://html.spec.whatwg.org/multipage/
+        form-control-infrastructure.html#multipart-form-data
+
+    :param name:
+        The name of the parameter, an ASCII-only ``str``.
+    :param value:
+        The value of the parameter, a ``str`` or UTF-8 encoded
+        ``bytes``.
+    :returns:
+        A string ``name="value"`` with the escaped value.
+
+    .. versionchanged:: 2.0.0
+        Matches the WHATWG HTML Standard as of 2021/06/10. Control
+        characters are no longer percent encoded.
+
+    .. versionchanged:: 2.0.0
+        Renamed from ``format_header_param_html5`` and
+        ``format_header_param``. The old names will be removed in
+        urllib3 v2.1.0.
+    """
+    if isinstance(value, bytes):
+        value = value.decode("utf-8")
+
+    # percent encode \n \r "
+    value = value.translate({10: "%0A", 13: "%0D", 34: "%22"})
+    return f'{name}="{value}"'
+
+
+def format_header_param_html5(name: str, value: _TYPE_FIELD_VALUE) -> str:
+    """
+    .. deprecated:: 2.0.0
+        Renamed to :func:`format_multipart_header_param`. Will be
+        removed in urllib3 v2.1.0.
+    """
+    import warnings
+
+    warnings.warn(
+        "'format_header_param_html5' has been renamed to "
+        "'format_multipart_header_param'. The old name will be "
+        "removed in urllib3 v2.1.0.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
+    return format_multipart_header_param(name, value)
+
+
+def format_header_param(name: str, value: _TYPE_FIELD_VALUE) -> str:
+    """
+    .. deprecated:: 2.0.0
+        Renamed to :func:`format_multipart_header_param`. Will be
+        removed in urllib3 v2.1.0.
+    """
+    import warnings
+
+    warnings.warn(
+        "'format_header_param' has been renamed to "
+        "'format_multipart_header_param'. The old name will be "
+        "removed in urllib3 v2.1.0.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
+    return format_multipart_header_param(name, value)
+
+
+class RequestField:
+    """
+    A data container for request body parameters.
+
+    :param name:
+        The name of this request field. Must be unicode.
+    :param data:
+        The data/value body.
+    :param filename:
+        An optional filename of the request field. Must be unicode.
+    :param headers:
+        An optional dict-like object of headers to initially use for the field.
+
+    .. versionchanged:: 2.0.0
+        The ``header_formatter`` parameter is deprecated and will
+        be removed in urllib3 v2.1.0.
+    """
+
+    def __init__(
+        self,
+        name: str,
+        data: _TYPE_FIELD_VALUE,
+        filename: str | None = None,
+        headers: typing.Mapping[str, str] | None = None,
+        header_formatter: typing.Callable[[str, _TYPE_FIELD_VALUE], str] | None = None,
+    ):
+        self._name = name
+        self._filename = filename
+        self.data = data
+        self.headers: dict[str, str | None] = {}
+        if headers:
+            self.headers = dict(headers)
+
+        if header_formatter is not None:
+            import warnings
+
+            warnings.warn(
+                "The 'header_formatter' parameter is deprecated and "
+                "will be removed in urllib3 v2.1.0.",
+                DeprecationWarning,
+                stacklevel=2,
+            )
+            self.header_formatter = header_formatter
+        else:
+            self.header_formatter = format_multipart_header_param
+
+    @classmethod
+    def from_tuples(
+        cls,
+        fieldname: str,
+        value: _TYPE_FIELD_VALUE_TUPLE,
+        header_formatter: typing.Callable[[str, _TYPE_FIELD_VALUE], str] | None = None,
+    ) -> RequestField:
+        """
+        A :class:`~urllib3.fields.RequestField` factory from old-style tuple parameters.
+
+        Supports constructing :class:`~urllib3.fields.RequestField` from
+        parameter of key/value strings AND key/filetuple. A filetuple is a
+        (filename, data, MIME type) tuple where the MIME type is optional.
+        For example::
+
+            'foo': 'bar',
+            'fakefile': ('foofile.txt', 'contents of foofile'),
+            'realfile': ('barfile.txt', open('realfile').read()),
+            'typedfile': ('bazfile.bin', open('bazfile').read(), 'image/jpeg'),
+            'nonamefile': 'contents of nonamefile field',
+
+        Field names and filenames must be unicode.
+        """
+        filename: str | None
+        content_type: str | None
+        data: _TYPE_FIELD_VALUE
+
+        if isinstance(value, tuple):
+            if len(value) == 3:
+                filename, data, content_type = value
+            else:
+                filename, data = value
+                content_type = guess_content_type(filename)
+        else:
+            filename = None
+            content_type = None
+            data = value
+
+        request_param = cls(
+            fieldname, data, filename=filename, header_formatter=header_formatter
+        )
+        request_param.make_multipart(content_type=content_type)
+
+        return request_param
+
+    def _render_part(self, name: str, value: _TYPE_FIELD_VALUE) -> str:
+        """
+        Override this method to change how each multipart header
+        parameter is formatted. By default, this calls
+        :func:`format_multipart_header_param`.
+
+        :param name:
+            The name of the parameter, an ASCII-only ``str``.
+        :param value:
+            The value of the parameter, a ``str`` or UTF-8 encoded
+            ``bytes``.
+
+        :meta public:
+        """
+        return self.header_formatter(name, value)
+
+    def _render_parts(
+        self,
+        header_parts: (
+            dict[str, _TYPE_FIELD_VALUE | None]
+            | typing.Sequence[tuple[str, _TYPE_FIELD_VALUE | None]]
+        ),
+    ) -> str:
+        """
+        Helper function to format and quote a single header.
+
+        Useful for single headers that are composed of multiple items. E.g.,
+        'Content-Disposition' fields.
+
+        :param header_parts:
+            A sequence of (k, v) tuples or a :class:`dict` of (k, v) to format
+            as `k1="v1"; k2="v2"; ...`.
+        """
+        iterable: typing.Iterable[tuple[str, _TYPE_FIELD_VALUE | None]]
+
+        parts = []
+        if isinstance(header_parts, dict):
+            iterable = header_parts.items()
+        else:
+            iterable = header_parts
+
+        for name, value in iterable:
+            if value is not None:
+                parts.append(self._render_part(name, value))
+
+        return "; ".join(parts)
+
+    def render_headers(self) -> str:
+        """
+        Renders the headers for this request field.
+        """
+        lines = []
+
+        sort_keys = ["Content-Disposition", "Content-Type", "Content-Location"]
+        for sort_key in sort_keys:
+            if self.headers.get(sort_key, False):
+                lines.append(f"{sort_key}: {self.headers[sort_key]}")
+
+        for header_name, header_value in self.headers.items():
+            if header_name not in sort_keys:
+                if header_value:
+                    lines.append(f"{header_name}: {header_value}")
+
+        lines.append("\r\n")
+        return "\r\n".join(lines)
+
+    def make_multipart(
+        self,
+        content_disposition: str | None = None,
+        content_type: str | None = None,
+        content_location: str | None = None,
+    ) -> None:
+        """
+        Makes this request field into a multipart request field.
+
+        This method overrides "Content-Disposition", "Content-Type" and
+        "Content-Location" headers to the request parameter.
+
+        :param content_disposition:
+            The 'Content-Disposition' of the request body. Defaults to 'form-data'
+        :param content_type:
+            The 'Content-Type' of the request body.
+        :param content_location:
+            The 'Content-Location' of the request body.
+
+        """
+        content_disposition = (content_disposition or "form-data") + "; ".join(
+            [
+                "",
+                self._render_parts(
+                    (("name", self._name), ("filename", self._filename))
+                ),
+            ]
+        )
+
+        self.headers["Content-Disposition"] = content_disposition
+        self.headers["Content-Type"] = content_type
+        self.headers["Content-Location"] = content_location

venv/lib/python3.10/site-packages/urllib3/filepost.py

@@ -0,0 +1,89 @@
+from __future__ import annotations
+
+import binascii
+import codecs
+import os
+import typing
+from io import BytesIO
+
+from .fields import _TYPE_FIELD_VALUE_TUPLE, RequestField
+
+writer = codecs.lookup("utf-8")[3]
+
+_TYPE_FIELDS_SEQUENCE = typing.Sequence[
+    typing.Union[typing.Tuple[str, _TYPE_FIELD_VALUE_TUPLE], RequestField]
+]
+_TYPE_FIELDS = typing.Union[
+    _TYPE_FIELDS_SEQUENCE,
+    typing.Mapping[str, _TYPE_FIELD_VALUE_TUPLE],
+]
+
+
+def choose_boundary() -> str:
+    """
+    Our embarrassingly-simple replacement for mimetools.choose_boundary.
+    """
+    return binascii.hexlify(os.urandom(16)).decode()
+
+
+def iter_field_objects(fields: _TYPE_FIELDS) -> typing.Iterable[RequestField]:
+    """
+    Iterate over fields.
+
+    Supports list of (k, v) tuples and dicts, and lists of
+    :class:`~urllib3.fields.RequestField`.
+
+    """
+    iterable: typing.Iterable[RequestField | tuple[str, _TYPE_FIELD_VALUE_TUPLE]]
+
+    if isinstance(fields, typing.Mapping):
+        iterable = fields.items()
+    else:
+        iterable = fields
+
+    for field in iterable:
+        if isinstance(field, RequestField):
+            yield field
+        else:
+            yield RequestField.from_tuples(*field)
+
+
+def encode_multipart_formdata(
+    fields: _TYPE_FIELDS, boundary: str | None = None
+) -> tuple[bytes, str]:
+    """
+    Encode a dictionary of ``fields`` using the multipart/form-data MIME format.
+
+    :param fields:
+        Dictionary of fields or list of (key, :class:`~urllib3.fields.RequestField`).
+        Values are processed by :func:`urllib3.fields.RequestField.from_tuples`.
+
+    :param boundary:
+        If not specified, then a random boundary will be generated using
+        :func:`urllib3.filepost.choose_boundary`.
+    """
+    body = BytesIO()
+    if boundary is None:
+        boundary = choose_boundary()
+
+    for field in iter_field_objects(fields):
+        body.write(f"--{boundary}\r\n".encode("latin-1"))
+
+        writer(body).write(field.render_headers())
+        data = field.data
+
+        if isinstance(data, int):
+            data = str(data)  # Backwards compatibility
+
+        if isinstance(data, str):
+            writer(body).write(data)
+        else:
+            body.write(data)
+
+        body.write(b"\r\n")
+
+    body.write(f"--{boundary}--\r\n".encode("latin-1"))
+
+    content_type = f"multipart/form-data; boundary={boundary}"
+
+    return body.getvalue(), content_type

venv/lib/python3.10/site-packages/urllib3/http2.py

@@ -0,0 +1,229 @@
+from __future__ import annotations
+
+import threading
+import types
+import typing
+
+import h2.config  # type: ignore[import-untyped]
+import h2.connection  # type: ignore[import-untyped]
+import h2.events  # type: ignore[import-untyped]
+
+import urllib3.connection
+import urllib3.util.ssl_
+from urllib3.response import BaseHTTPResponse
+
+from ._collections import HTTPHeaderDict
+from .connection import HTTPSConnection
+from .connectionpool import HTTPSConnectionPool
+
+orig_HTTPSConnection = HTTPSConnection
+
+T = typing.TypeVar("T")
+
+
+class _LockedObject(typing.Generic[T]):
+    """
+    A wrapper class that hides a specific object behind a lock.
+
+    The goal here is to provide a simple way to protect access to an object
+    that cannot safely be simultaneously accessed from multiple threads. The
+    intended use of this class is simple: take hold of it with a context
+    manager, which returns the protected object.
+    """
+
+    def __init__(self, obj: T):
+        self.lock = threading.RLock()
+        self._obj = obj
+
+    def __enter__(self) -> T:
+        self.lock.acquire()
+        return self._obj
+
+    def __exit__(
+        self,
+        exc_type: type[BaseException] | None,
+        exc_val: BaseException | None,
+        exc_tb: types.TracebackType | None,
+    ) -> None:
+        self.lock.release()
+
+
+class HTTP2Connection(HTTPSConnection):
+    def __init__(
+        self, host: str, port: int | None = None, **kwargs: typing.Any
+    ) -> None:
+        self._h2_conn = self._new_h2_conn()
+        self._h2_stream: int | None = None
+        self._h2_headers: list[tuple[bytes, bytes]] = []
+
+        if "proxy" in kwargs or "proxy_config" in kwargs:  # Defensive:
+            raise NotImplementedError("Proxies aren't supported with HTTP/2")
+
+        super().__init__(host, port, **kwargs)
+
+    def _new_h2_conn(self) -> _LockedObject[h2.connection.H2Connection]:
+        config = h2.config.H2Configuration(client_side=True)
+        return _LockedObject(h2.connection.H2Connection(config=config))
+
+    def connect(self) -> None:
+        super().connect()
+
+        with self._h2_conn as h2_conn:
+            h2_conn.initiate_connection()
+            self.sock.sendall(h2_conn.data_to_send())
+
+    def putrequest(
+        self,
+        method: str,
+        url: str,
+        skip_host: bool = False,
+        skip_accept_encoding: bool = False,
+    ) -> None:
+        with self._h2_conn as h2_conn:
+            self._request_url = url
+            self._h2_stream = h2_conn.get_next_available_stream_id()
+
+            if ":" in self.host:
+                authority = f"[{self.host}]:{self.port or 443}"
+            else:
+                authority = f"{self.host}:{self.port or 443}"
+
+            self._h2_headers.extend(
+                (
+                    (b":scheme", b"https"),
+                    (b":method", method.encode()),
+                    (b":authority", authority.encode()),
+                    (b":path", url.encode()),
+                )
+            )
+
+    def putheader(self, header: str, *values: str) -> None:  # type: ignore[override]
+        for value in values:
+            self._h2_headers.append(
+                (header.encode("utf-8").lower(), value.encode("utf-8"))
+            )
+
+    def endheaders(self) -> None:  # type: ignore[override]
+        with self._h2_conn as h2_conn:
+            h2_conn.send_headers(
+                stream_id=self._h2_stream,
+                headers=self._h2_headers,
+                end_stream=True,
+            )
+            if data_to_send := h2_conn.data_to_send():
+                self.sock.sendall(data_to_send)
+
+    def send(self, data: bytes) -> None:  # type: ignore[override]  # Defensive:
+        if not data:
+            return
+        raise NotImplementedError("Sending data isn't supported yet")
+
+    def getresponse(  # type: ignore[override]
+        self,
+    ) -> HTTP2Response:
+        status = None
+        data = bytearray()
+        with self._h2_conn as h2_conn:
+            end_stream = False
+            while not end_stream:
+                # TODO: Arbitrary read value.
+                if received_data := self.sock.recv(65535):
+                    events = h2_conn.receive_data(received_data)
+                    for event in events:
+                        if isinstance(event, h2.events.ResponseReceived):
+                            headers = HTTPHeaderDict()
+                            for header, value in event.headers:
+                                if header == b":status":
+                                    status = int(value.decode())
+                                else:
+                                    headers.add(
+                                        header.decode("ascii"), value.decode("ascii")
+                                    )
+
+                        elif isinstance(event, h2.events.DataReceived):
+                            data += event.data
+                            h2_conn.acknowledge_received_data(
+                                event.flow_controlled_length, event.stream_id
+                            )
+
+                        elif isinstance(event, h2.events.StreamEnded):
+                            end_stream = True
+
+                if data_to_send := h2_conn.data_to_send():
+                    self.sock.sendall(data_to_send)
+
+        # We always close to not have to handle connection management.
+        self.close()
+
+        assert status is not None
+        return HTTP2Response(
+            status=status,
+            headers=headers,
+            request_url=self._request_url,
+            data=bytes(data),
+        )
+
+    def close(self) -> None:
+        with self._h2_conn as h2_conn:
+            try:
+                h2_conn.close_connection()
+                if data := h2_conn.data_to_send():
+                    self.sock.sendall(data)
+            except Exception:
+                pass
+
+        # Reset all our HTTP/2 connection state.
+        self._h2_conn = self._new_h2_conn()
+        self._h2_stream = None
+        self._h2_headers = []
+
+        super().close()
+
+
+class HTTP2Response(BaseHTTPResponse):
+    # TODO: This is a woefully incomplete response object, but works for non-streaming.
+    def __init__(
+        self,
+        status: int,
+        headers: HTTPHeaderDict,
+        request_url: str,
+        data: bytes,
+        decode_content: bool = False,  # TODO: support decoding
+    ) -> None:
+        super().__init__(
+            status=status,
+            headers=headers,
+            # Following CPython, we map HTTP versions to major * 10 + minor integers
+            version=20,
+            # No reason phrase in HTTP/2
+            reason=None,
+            decode_content=decode_content,
+            request_url=request_url,
+        )
+        self._data = data
+        self.length_remaining = 0
+
+    @property
+    def data(self) -> bytes:
+        return self._data
+
+    def get_redirect_location(self) -> None:
+        return None
+
+    def close(self) -> None:
+        pass
+
+
+def inject_into_urllib3() -> None:
+    HTTPSConnectionPool.ConnectionCls = HTTP2Connection
+    urllib3.connection.HTTPSConnection = HTTP2Connection  # type: ignore[misc]
+
+    # TODO: Offer 'http/1.1' as well, but for testing purposes this is handy.
+    urllib3.util.ssl_.ALPN_PROTOCOLS = ["h2"]
+
+
+def extract_from_urllib3() -> None:
+    HTTPSConnectionPool.ConnectionCls = orig_HTTPSConnection
+    urllib3.connection.HTTPSConnection = orig_HTTPSConnection  # type: ignore[misc]
+
+    urllib3.util.ssl_.ALPN_PROTOCOLS = ["http/1.1"]

venv/lib/python3.10/site-packages/urllib3/poolmanager.py

@@ -0,0 +1,638 @@
+from __future__ import annotations
+
+import functools
+import logging
+import typing
+import warnings
+from types import TracebackType
+from urllib.parse import urljoin
+
+from ._collections import HTTPHeaderDict, RecentlyUsedContainer
+from ._request_methods import RequestMethods
+from .connection import ProxyConfig
+from .connectionpool import HTTPConnectionPool, HTTPSConnectionPool, port_by_scheme
+from .exceptions import (
+    LocationValueError,
+    MaxRetryError,
+    ProxySchemeUnknown,
+    URLSchemeUnknown,
+)
+from .response import BaseHTTPResponse
+from .util.connection import _TYPE_SOCKET_OPTIONS
+from .util.proxy import connection_requires_http_tunnel
+from .util.retry import Retry
+from .util.timeout import Timeout
+from .util.url import Url, parse_url
+
+if typing.TYPE_CHECKING:
+    import ssl
+    from typing import Literal
+
+__all__ = ["PoolManager", "ProxyManager", "proxy_from_url"]
+
+
+log = logging.getLogger(__name__)
+
+SSL_KEYWORDS = (
+    "key_file",
+    "cert_file",
+    "cert_reqs",
+    "ca_certs",
+    "ca_cert_data",
+    "ssl_version",
+    "ssl_minimum_version",
+    "ssl_maximum_version",
+    "ca_cert_dir",
+    "ssl_context",
+    "key_password",
+    "server_hostname",
+)
+# Default value for `blocksize` - a new parameter introduced to
+# http.client.HTTPConnection & http.client.HTTPSConnection in Python 3.7
+_DEFAULT_BLOCKSIZE = 16384
+
+_SelfT = typing.TypeVar("_SelfT")
+
+
+class PoolKey(typing.NamedTuple):
+    """
+    All known keyword arguments that could be provided to the pool manager, its
+    pools, or the underlying connections.
+
+    All custom key schemes should include the fields in this key at a minimum.
+    """
+
+    key_scheme: str
+    key_host: str
+    key_port: int | None
+    key_timeout: Timeout | float | int | None
+    key_retries: Retry | bool | int | None
+    key_block: bool | None
+    key_source_address: tuple[str, int] | None
+    key_key_file: str | None
+    key_key_password: str | None
+    key_cert_file: str | None
+    key_cert_reqs: str | None
+    key_ca_certs: str | None
+    key_ca_cert_data: str | bytes | None
+    key_ssl_version: int | str | None
+    key_ssl_minimum_version: ssl.TLSVersion | None
+    key_ssl_maximum_version: ssl.TLSVersion | None
+    key_ca_cert_dir: str | None
+    key_ssl_context: ssl.SSLContext | None
+    key_maxsize: int | None
+    key_headers: frozenset[tuple[str, str]] | None
+    key__proxy: Url | None
+    key__proxy_headers: frozenset[tuple[str, str]] | None
+    key__proxy_config: ProxyConfig | None
+    key_socket_options: _TYPE_SOCKET_OPTIONS | None
+    key__socks_options: frozenset[tuple[str, str]] | None
+    key_assert_hostname: bool | str | None
+    key_assert_fingerprint: str | None
+    key_server_hostname: str | None
+    key_blocksize: int | None
+
+
+def _default_key_normalizer(
+    key_class: type[PoolKey], request_context: dict[str, typing.Any]
+) -> PoolKey:
+    """
+    Create a pool key out of a request context dictionary.
+
+    According to RFC 3986, both the scheme and host are case-insensitive.
+    Therefore, this function normalizes both before constructing the pool
+    key for an HTTPS request. If you wish to change this behaviour, provide
+    alternate callables to ``key_fn_by_scheme``.
+
+    :param key_class:
+        The class to use when constructing the key. This should be a namedtuple
+        with the ``scheme`` and ``host`` keys at a minimum.
+    :type  key_class: namedtuple
+    :param request_context:
+        A dictionary-like object that contain the context for a request.
+    :type  request_context: dict
+
+    :return: A namedtuple that can be used as a connection pool key.
+    :rtype:  PoolKey
+    """
+    # Since we mutate the dictionary, make a copy first
+    context = request_context.copy()
+    context["scheme"] = context["scheme"].lower()
+    context["host"] = context["host"].lower()
+
+    # These are both dictionaries and need to be transformed into frozensets
+    for key in ("headers", "_proxy_headers", "_socks_options"):
+        if key in context and context[key] is not None:
+            context[key] = frozenset(context[key].items())
+
+    # The socket_options key may be a list and needs to be transformed into a
+    # tuple.
+    socket_opts = context.get("socket_options")
+    if socket_opts is not None:
+        context["socket_options"] = tuple(socket_opts)
+
+    # Map the kwargs to the names in the namedtuple - this is necessary since
+    # namedtuples can't have fields starting with '_'.
+    for key in list(context.keys()):
+        context["key_" + key] = context.pop(key)
+
+    # Default to ``None`` for keys missing from the context
+    for field in key_class._fields:
+        if field not in context:
+            context[field] = None
+
+    # Default key_blocksize to _DEFAULT_BLOCKSIZE if missing from the context
+    if context.get("key_blocksize") is None:
+        context["key_blocksize"] = _DEFAULT_BLOCKSIZE
+
+    return key_class(**context)
+
+
+#: A dictionary that maps a scheme to a callable that creates a pool key.
+#: This can be used to alter the way pool keys are constructed, if desired.
+#: Each PoolManager makes a copy of this dictionary so they can be configured
+#: globally here, or individually on the instance.
+key_fn_by_scheme = {
+    "http": functools.partial(_default_key_normalizer, PoolKey),
+    "https": functools.partial(_default_key_normalizer, PoolKey),
+}
+
+pool_classes_by_scheme = {"http": HTTPConnectionPool, "https": HTTPSConnectionPool}
+
+
+class PoolManager(RequestMethods):
+    """
+    Allows for arbitrary requests while transparently keeping track of
+    necessary connection pools for you.
+
+    :param num_pools:
+        Number of connection pools to cache before discarding the least
+        recently used pool.
+
+    :param headers:
+        Headers to include with all requests, unless other headers are given
+        explicitly.
+
+    :param \\**connection_pool_kw:
+        Additional parameters are used to create fresh
+        :class:`urllib3.connectionpool.ConnectionPool` instances.
+
+    Example:
+
+    .. code-block:: python
+
+        import urllib3
+
+        http = urllib3.PoolManager(num_pools=2)
+
+        resp1 = http.request("GET", "https://google.com/")
+        resp2 = http.request("GET", "https://google.com/mail")
+        resp3 = http.request("GET", "https://yahoo.com/")
+
+        print(len(http.pools))
+        # 2
+
+    """
+
+    proxy: Url | None = None
+    proxy_config: ProxyConfig | None = None
+
+    def __init__(
+        self,
+        num_pools: int = 10,
+        headers: typing.Mapping[str, str] | None = None,
+        **connection_pool_kw: typing.Any,
+    ) -> None:
+        super().__init__(headers)
+        self.connection_pool_kw = connection_pool_kw
+
+        self.pools: RecentlyUsedContainer[PoolKey, HTTPConnectionPool]
+        self.pools = RecentlyUsedContainer(num_pools)
+
+        # Locally set the pool classes and keys so other PoolManagers can
+        # override them.
+        self.pool_classes_by_scheme = pool_classes_by_scheme
+        self.key_fn_by_scheme = key_fn_by_scheme.copy()
+
+    def __enter__(self: _SelfT) -> _SelfT:
+        return self
+
+    def __exit__(
+        self,
+        exc_type: type[BaseException] | None,
+        exc_val: BaseException | None,
+        exc_tb: TracebackType | None,
+    ) -> Literal[False]:
+        self.clear()
+        # Return False to re-raise any potential exceptions
+        return False
+
+    def _new_pool(
+        self,
+        scheme: str,
+        host: str,
+        port: int,
+        request_context: dict[str, typing.Any] | None = None,
+    ) -> HTTPConnectionPool:
+        """
+        Create a new :class:`urllib3.connectionpool.ConnectionPool` based on host, port, scheme, and
+        any additional pool keyword arguments.
+
+        If ``request_context`` is provided, it is provided as keyword arguments
+        to the pool class used. This method is used to actually create the
+        connection pools handed out by :meth:`connection_from_url` and
+        companion methods. It is intended to be overridden for customization.
+        """
+        pool_cls: type[HTTPConnectionPool] = self.pool_classes_by_scheme[scheme]
+        if request_context is None:
+            request_context = self.connection_pool_kw.copy()
+
+        # Default blocksize to _DEFAULT_BLOCKSIZE if missing or explicitly
+        # set to 'None' in the request_context.
+        if request_context.get("blocksize") is None:
+            request_context["blocksize"] = _DEFAULT_BLOCKSIZE
+
+        # Although the context has everything necessary to create the pool,
+        # this function has historically only used the scheme, host, and port
+        # in the positional args. When an API change is acceptable these can
+        # be removed.
+        for key in ("scheme", "host", "port"):
+            request_context.pop(key, None)
+
+        if scheme == "http":
+            for kw in SSL_KEYWORDS:
+                request_context.pop(kw, None)
+
+        return pool_cls(host, port, **request_context)
+
+    def clear(self) -> None:
+        """
+        Empty our store of pools and direct them all to close.
+
+        This will not affect in-flight connections, but they will not be
+        re-used after completion.
+        """
+        self.pools.clear()
+
+    def connection_from_host(
+        self,
+        host: str | None,
+        port: int | None = None,
+        scheme: str | None = "http",
+        pool_kwargs: dict[str, typing.Any] | None = None,
+    ) -> HTTPConnectionPool:
+        """
+        Get a :class:`urllib3.connectionpool.ConnectionPool` based on the host, port, and scheme.
+
+        If ``port`` isn't given, it will be derived from the ``scheme`` using
+        ``urllib3.connectionpool.port_by_scheme``. If ``pool_kwargs`` is
+        provided, it is merged with the instance's ``connection_pool_kw``
+        variable and used to create the new connection pool, if one is
+        needed.
+        """
+
+        if not host:
+            raise LocationValueError("No host specified.")
+
+        request_context = self._merge_pool_kwargs(pool_kwargs)
+        request_context["scheme"] = scheme or "http"
+        if not port:
+            port = port_by_scheme.get(request_context["scheme"].lower(), 80)
+        request_context["port"] = port
+        request_context["host"] = host
+
+        return self.connection_from_context(request_context)
+
+    def connection_from_context(
+        self, request_context: dict[str, typing.Any]
+    ) -> HTTPConnectionPool:
+        """
+        Get a :class:`urllib3.connectionpool.ConnectionPool` based on the request context.
+
+        ``request_context`` must at least contain the ``scheme`` key and its
+        value must be a key in ``key_fn_by_scheme`` instance variable.
+        """
+        if "strict" in request_context:
+            warnings.warn(
+                "The 'strict' parameter is no longer needed on Python 3+. "
+                "This will raise an error in urllib3 v2.1.0.",
+                DeprecationWarning,
+            )
+            request_context.pop("strict")
+
+        scheme = request_context["scheme"].lower()
+        pool_key_constructor = self.key_fn_by_scheme.get(scheme)
+        if not pool_key_constructor:
+            raise URLSchemeUnknown(scheme)
+        pool_key = pool_key_constructor(request_context)
+
+        return self.connection_from_pool_key(pool_key, request_context=request_context)
+
+    def connection_from_pool_key(
+        self, pool_key: PoolKey, request_context: dict[str, typing.Any]
+    ) -> HTTPConnectionPool:
+        """
+        Get a :class:`urllib3.connectionpool.ConnectionPool` based on the provided pool key.
+
+        ``pool_key`` should be a namedtuple that only contains immutable
+        objects. At a minimum it must have the ``scheme``, ``host``, and
+        ``port`` fields.
+        """
+        with self.pools.lock:
+            # If the scheme, host, or port doesn't match existing open
+            # connections, open a new ConnectionPool.
+            pool = self.pools.get(pool_key)
+            if pool:
+                return pool
+
+            # Make a fresh ConnectionPool of the desired type
+            scheme = request_context["scheme"]
+            host = request_context["host"]
+            port = request_context["port"]
+            pool = self._new_pool(scheme, host, port, request_context=request_context)
+            self.pools[pool_key] = pool
+
+        return pool
+
+    def connection_from_url(
+        self, url: str, pool_kwargs: dict[str, typing.Any] | None = None
+    ) -> HTTPConnectionPool:
+        """
+        Similar to :func:`urllib3.connectionpool.connection_from_url`.
+
+        If ``pool_kwargs`` is not provided and a new pool needs to be
+        constructed, ``self.connection_pool_kw`` is used to initialize
+        the :class:`urllib3.connectionpool.ConnectionPool`. If ``pool_kwargs``
+        is provided, it is used instead. Note that if a new pool does not
+        need to be created for the request, the provided ``pool_kwargs`` are
+        not used.
+        """
+        u = parse_url(url)
+        return self.connection_from_host(
+            u.host, port=u.port, scheme=u.scheme, pool_kwargs=pool_kwargs
+        )
+
+    def _merge_pool_kwargs(
+        self, override: dict[str, typing.Any] | None
+    ) -> dict[str, typing.Any]:
+        """
+        Merge a dictionary of override values for self.connection_pool_kw.
+
+        This does not modify self.connection_pool_kw and returns a new dict.
+        Any keys in the override dictionary with a value of ``None`` are
+        removed from the merged dictionary.
+        """
+        base_pool_kwargs = self.connection_pool_kw.copy()
+        if override:
+            for key, value in override.items():
+                if value is None:
+                    try:
+                        del base_pool_kwargs[key]
+                    except KeyError:
+                        pass
+                else:
+                    base_pool_kwargs[key] = value
+        return base_pool_kwargs
+
+    def _proxy_requires_url_absolute_form(self, parsed_url: Url) -> bool:
+        """
+        Indicates if the proxy requires the complete destination URL in the
+        request.  Normally this is only needed when not using an HTTP CONNECT
+        tunnel.
+        """
+        if self.proxy is None:
+            return False
+
+        return not connection_requires_http_tunnel(
+            self.proxy, self.proxy_config, parsed_url.scheme
+        )
+
+    def urlopen(  # type: ignore[override]
+        self, method: str, url: str, redirect: bool = True, **kw: typing.Any
+    ) -> BaseHTTPResponse:
+        """
+        Same as :meth:`urllib3.HTTPConnectionPool.urlopen`
+        with custom cross-host redirect logic and only sends the request-uri
+        portion of the ``url``.
+
+        The given ``url`` parameter must be absolute, such that an appropriate
+        :class:`urllib3.connectionpool.ConnectionPool` can be chosen for it.
+        """
+        u = parse_url(url)
+
+        if u.scheme is None:
+            warnings.warn(
+                "URLs without a scheme (ie 'https://') are deprecated and will raise an error "
+                "in a future version of urllib3. To avoid this DeprecationWarning ensure all URLs "
+                "start with 'https://' or 'http://'. Read more in this issue: "
+                "https://github.com/urllib3/urllib3/issues/2920",
+                category=DeprecationWarning,
+                stacklevel=2,
+            )
+
+        conn = self.connection_from_host(u.host, port=u.port, scheme=u.scheme)
+
+        kw["assert_same_host"] = False
+        kw["redirect"] = False
+
+        if "headers" not in kw:
+            kw["headers"] = self.headers
+
+        if self._proxy_requires_url_absolute_form(u):
+            response = conn.urlopen(method, url, **kw)
+        else:
+            response = conn.urlopen(method, u.request_uri, **kw)
+
+        redirect_location = redirect and response.get_redirect_location()
+        if not redirect_location:
+            return response
+
+        # Support relative URLs for redirecting.
+        redirect_location = urljoin(url, redirect_location)
+
+        if response.status == 303:
+            # Change the method according to RFC 9110, Section 15.4.4.
+            method = "GET"
+            # And lose the body not to transfer anything sensitive.
+            kw["body"] = None
+            kw["headers"] = HTTPHeaderDict(kw["headers"])._prepare_for_method_change()
+
+        retries = kw.get("retries")
+        if not isinstance(retries, Retry):
+            retries = Retry.from_int(retries, redirect=redirect)
+
+        # Strip headers marked as unsafe to forward to the redirected location.
+        # Check remove_headers_on_redirect to avoid a potential network call within
+        # conn.is_same_host() which may use socket.gethostbyname() in the future.
+        if retries.remove_headers_on_redirect and not conn.is_same_host(
+            redirect_location
+        ):
+            new_headers = kw["headers"].copy()
+            for header in kw["headers"]:
+                if header.lower() in retries.remove_headers_on_redirect:
+                    new_headers.pop(header, None)
+            kw["headers"] = new_headers
+
+        try:
+            retries = retries.increment(method, url, response=response, _pool=conn)
+        except MaxRetryError:
+            if retries.raise_on_redirect:
+                response.drain_conn()
+                raise
+            return response
+
+        kw["retries"] = retries
+        kw["redirect"] = redirect
+
+        log.info("Redirecting %s -> %s", url, redirect_location)
+
+        response.drain_conn()
+        return self.urlopen(method, redirect_location, **kw)
+
+
+class ProxyManager(PoolManager):
+    """
+    Behaves just like :class:`PoolManager`, but sends all requests through
+    the defined proxy, using the CONNECT method for HTTPS URLs.
+
+    :param proxy_url:
+        The URL of the proxy to be used.
+
+    :param proxy_headers:
+        A dictionary containing headers that will be sent to the proxy. In case
+        of HTTP they are being sent with each request, while in the
+        HTTPS/CONNECT case they are sent only once. Could be used for proxy
+        authentication.
+
+    :param proxy_ssl_context:
+        The proxy SSL context is used to establish the TLS connection to the
+        proxy when using HTTPS proxies.
+
+    :param use_forwarding_for_https:
+        (Defaults to False) If set to True will forward requests to the HTTPS
+        proxy to be made on behalf of the client instead of creating a TLS
+        tunnel via the CONNECT method. **Enabling this flag means that request
+        and response headers and content will be visible from the HTTPS proxy**
+        whereas tunneling keeps request and response headers and content
+        private.  IP address, target hostname, SNI, and port are always visible
+        to an HTTPS proxy even when this flag is disabled.
+
+    :param proxy_assert_hostname:
+        The hostname of the certificate to verify against.
+
+    :param proxy_assert_fingerprint:
+        The fingerprint of the certificate to verify against.
+
+    Example:
+
+    .. code-block:: python
+
+        import urllib3
+
+        proxy = urllib3.ProxyManager("https://localhost:3128/")
+
+        resp1 = proxy.request("GET", "https://google.com/")
+        resp2 = proxy.request("GET", "https://httpbin.org/")
+
+        print(len(proxy.pools))
+        # 1
+
+        resp3 = proxy.request("GET", "https://httpbin.org/")
+        resp4 = proxy.request("GET", "https://twitter.com/")
+
+        print(len(proxy.pools))
+        # 3
+
+    """
+
+    def __init__(
+        self,
+        proxy_url: str,
+        num_pools: int = 10,
+        headers: typing.Mapping[str, str] | None = None,
+        proxy_headers: typing.Mapping[str, str] | None = None,
+        proxy_ssl_context: ssl.SSLContext | None = None,
+        use_forwarding_for_https: bool = False,
+        proxy_assert_hostname: None | str | Literal[False] = None,
+        proxy_assert_fingerprint: str | None = None,
+        **connection_pool_kw: typing.Any,
+    ) -> None:
+        if isinstance(proxy_url, HTTPConnectionPool):
+            str_proxy_url = f"{proxy_url.scheme}://{proxy_url.host}:{proxy_url.port}"
+        else:
+            str_proxy_url = proxy_url
+        proxy = parse_url(str_proxy_url)
+
+        if proxy.scheme not in ("http", "https"):
+            raise ProxySchemeUnknown(proxy.scheme)
+
+        if not proxy.port:
+            port = port_by_scheme.get(proxy.scheme, 80)
+            proxy = proxy._replace(port=port)
+
+        self.proxy = proxy
+        self.proxy_headers = proxy_headers or {}
+        self.proxy_ssl_context = proxy_ssl_context
+        self.proxy_config = ProxyConfig(
+            proxy_ssl_context,
+            use_forwarding_for_https,
+            proxy_assert_hostname,
+            proxy_assert_fingerprint,
+        )
+
+        connection_pool_kw["_proxy"] = self.proxy
+        connection_pool_kw["_proxy_headers"] = self.proxy_headers
+        connection_pool_kw["_proxy_config"] = self.proxy_config
+
+        super().__init__(num_pools, headers, **connection_pool_kw)
+
+    def connection_from_host(
+        self,
+        host: str | None,
+        port: int | None = None,
+        scheme: str | None = "http",
+        pool_kwargs: dict[str, typing.Any] | None = None,
+    ) -> HTTPConnectionPool:
+        if scheme == "https":
+            return super().connection_from_host(
+                host, port, scheme, pool_kwargs=pool_kwargs
+            )
+
+        return super().connection_from_host(
+            self.proxy.host, self.proxy.port, self.proxy.scheme, pool_kwargs=pool_kwargs  # type: ignore[union-attr]
+        )
+
+    def _set_proxy_headers(
+        self, url: str, headers: typing.Mapping[str, str] | None = None
+    ) -> typing.Mapping[str, str]:
+        """
+        Sets headers needed by proxies: specifically, the Accept and Host
+        headers. Only sets headers not provided by the user.
+        """
+        headers_ = {"Accept": "*/*"}
+
+        netloc = parse_url(url).netloc
+        if netloc:
+            headers_["Host"] = netloc
+
+        if headers:
+            headers_.update(headers)
+        return headers_
+
+    def urlopen(  # type: ignore[override]
+        self, method: str, url: str, redirect: bool = True, **kw: typing.Any
+    ) -> BaseHTTPResponse:
+        "Same as HTTP(S)ConnectionPool.urlopen, ``url`` must be absolute."
+        u = parse_url(url)
+        if not connection_requires_http_tunnel(self.proxy, self.proxy_config, u.scheme):
+            # For connections using HTTP CONNECT, httplib sets the necessary
+            # headers on the CONNECT to the proxy. If we're not using CONNECT,
+            # we'll definitely need to set 'Host' at the very least.
+            headers = kw.get("headers", self.headers)
+            kw["headers"] = self._set_proxy_headers(url, headers)
+
+        return super().urlopen(method, url, redirect=redirect, **kw)
+
+
+def proxy_from_url(url: str, **kw: typing.Any) -> ProxyManager:
+    return ProxyManager(proxy_url=url, **kw)