fixed optional values

schemas.py

@@ -14,7 +14,7 @@ class ModelRequest(BaseModel):
 class ModelResponse(BaseModel): 
     request_id: Annotated[str, Field(default_factory=lambda: uuid4().hex)]
     ip: Annotated[Optional[IPvAnyAddress], Field(default=None)]
-    content: Annotated[str | None, Field(min_length=0, max_length=10000)]
+    content: Annotated[Optional[str], Field(min_length=0, max_length=10000,default=None)]
     created_at: datetime = datetime.now()
 
 
@@ -23,7 +23,7 @@ class TextModelRequest(ModelRequest):
     temperature: Annotated[float, Field(ge=0.0, le=1.0, default=0.0)]
 
 class TextModelResponse(ModelResponse):
-    tokens: Annotated[int|None, Field(ge=0)]
+    tokens: Annotated[Optional[int], Field(ge=0,default=None)]
 
 ImageSize = Annotated[tuple[PositiveInt, PositiveInt], "Width and height of an image in pixels"]
 SupportedModels = Annotated[
@@ -55,5 +55,5 @@ class ImageModelRequest(ModelRequest):
 
 class ImageModelResponse(ModelResponse): 
     size: ImageSize
-    url: Annotated[str, HttpUrl] | None = None
+    url: Annotated[Optional[HttpUrl], Field(default=None)]