fix: support list[pydantic.BaseModel] in response.parsed type annotation : Issue #886

[Adewale-1]

This PR fixes issue #886 by adding support for list[pydantic.BaseModel] in the parsed field's type annotation of GenerateContentResponse.

Problem

Currently, when using response_schema=list[SomeModel] in the API call, the code functionally works (returning a list of model objects), but mypy type checking fails because the type annotation doesn't include the possibility of a list of pydantic models.

This requires developers to use explicit type casting (as shown in PR #886), which reduces confidence in unit tests and type safety.

Solution

Added list[pydantic.BaseModel] to the Union type in the parsed field type annotation.

Testing

Added comprehensive tests in:

• test_parsed_list_support.py
• test_parsed_list_mypy.py
• test_live_client_and_list_type.py

Tests verify both runtime behavior and mypy type checking compatibility.

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[ghost]

@Adewale-1 looks like you will have to sign the contributor agreement for this PR to be accepted.

[janasangeetha]

Hey @Adewale-1
Can you please resolve conflicts? Thank you!