Add support for reading CSV file from web URL

isco.py

@@ -1,6 +1,7 @@
 """This module provides functionality for creating a hierarchy tree and a mapping from ISCO code to node name."""
 
 import csv
+import requests
 
 
 def create_hierarchy_dict(file: str) -> dict:
@@ -10,21 +11,27 @@ def create_hierarchy_dict(file: str) -> dict:
     A csv file with the ISCO-08 structure can be downloaded from the International Labour Organization (ILO) at [https://www.ilo.org/ilostat-files/ISCO/newdocs-08-2021/ISCO-08/ISCO-08 EN.csv](https://www.ilo.org/ilostat-files/ISCO/newdocs-08-2021/ISCO-08/ISCO-08%20EN.csv)
 
     Args:
-    - file: A string representing the path to the CSV file containing the 4-digit ISCO-08 codes.
+    - file: A string representing the path to the CSV file containing the 4-digit ISCO-08 codes. It can be a local path or a web URL.
 
     Returns:
     - A dictionary where keys are ISCO-08 unit codes and values are sets of their parent codes.
     """
     isco_hierarchy = {}
 
-    with open(file, newline="") as csvfile:
-        reader = csv.DictReader(csvfile)
-        for row in reader:
-            unit_code = row["unit"].zfill(4)
-            minor_code = unit_code[0:3]
-            sub_major_code = unit_code[0:2]
-            major_code = unit_code[0]
-            isco_hierarchy[unit_code] = {minor_code, major_code, sub_major_code}
+    if file.startswith("http://") or file.startswith("https://"):
+        response = requests.get(file)
+        lines = response.text.splitlines()
+    else:
+        with open(file, newline="") as csvfile:
+            lines = csvfile.readlines()
+
+    reader = csv.DictReader(lines)
+    for row in reader:
+        unit_code = row["unit"].zfill(4)
+        minor_code = unit_code[0:3]
+        sub_major_code = unit_code[0:2]
+        major_code = unit_code[0]
+        isco_hierarchy[unit_code] = {minor_code, major_code, sub_major_code}
 
     return isco_hierarchy