Address review feedback from @paxiaatucsdedu

- Fix mypy settings: revert warn_unused_ignores to true (match langchain-google standards)
- Remove unnecessary type: ignore comments (4 total across oci_generative_ai.py and oci_data_science.py)
- Remove duplicate test file test_openai_model.py (consolidated into test_openai_models.py)
- Update PR description to clarify Python 3.9 backwards compatibility via conditional dependencies

Author: fede-kamel

libs/oci/langchain_oci/chat_models/oci_data_science.py

@@ -780,7 +780,7 @@ def bind_tools(
         formatted_tools = [convert_to_openai_tool(tool) for tool in tools]
         if tool_choice is not None:
             kwargs["tool_choice"] = tool_choice
-        return super().bind(tools=formatted_tools, **kwargs)  # type: ignore[return-value]
+        return super().bind(tools=formatted_tools, **kwargs)
 
 
 class ChatOCIModelDeploymentVLLM(ChatOCIModelDeployment):

libs/oci/langchain_oci/chat_models/oci_generative_ai.py

@@ -1287,7 +1287,7 @@ def bind_tools(
                 )
             kwargs["is_parallel_tool_calls"] = True
 
-        return super().bind(tools=formatted_tools, **kwargs)  # type: ignore[return-value]
+        return super().bind(tools=formatted_tools, **kwargs)
 
     def with_structured_output(
         self,
@@ -1360,7 +1360,7 @@ def with_structured_output(
                     key_name=tool_name, first_tool_only=True
                 )
         elif method == "json_mode":
-            llm = self.bind(response_format={"type": "JSON_OBJECT"})  # type: ignore[assignment]
+            llm = self.bind(response_format={"type": "JSON_OBJECT"})
             output_parser = (
                 PydanticOutputParser(pydantic_object=schema)
                 if is_pydantic_schema
@@ -1384,7 +1384,7 @@ def with_structured_output(
                 json_schema=response_json_schema
             )
 
-            llm = self.bind(response_format=response_format_obj)  # type: ignore[assignment]
+            llm = self.bind(response_format=response_format_obj)
             if is_pydantic_schema:
                 output_parser = PydanticOutputParser(pydantic_object=schema)
             else:

libs/oci/pyproject.toml

@@ -98,7 +98,7 @@ show_error_context = true
 warn_redundant_casts = true
 warn_unreachable = true
 warn_unused_configs = true
-warn_unused_ignores = false
+warn_unused_ignores = true
 
 # Ignore missing imports only for specific untyped packages
 [[tool.mypy.overrides]]