solved = await solve_generator(
                call=call, stack=async_exit_stack, sub_values=sub_values
            )
        elif is_coroutine_callable(call):
            solved = await call(**sub_values)
        else:
            solved = await run_in_threadpool(call, **sub_values)
        if sub_dependant.name is not None:
            values[sub_dependant.name] = solved

index_sponsors_template = """
{% if sponsors %}
{% for sponsor in sponsors.gold -%}
<a href="{{ sponsor.url }}" target="_blank" title="{{ sponsor.title }}"><img src="{{ sponsor.img }}"></a>
{% endfor -%}
{%- for sponsor in sponsors.silver -%}
<a href="{{ sponsor.url }}" target="_blank" title="{{ sponsor.title }}"><img src="{{ sponsor.img }}"></a>
{% endfor %}
{% endif %}
"""


def generate_readme_content() -> str:

try:
    import email_validator

    assert email_validator  # make autoflake ignore the unused import
    from pydantic import EmailStr
except ImportError:  # pragma: no cover

    class EmailStr(str):  # type: ignore
        @classmethod
        def __get_validators__(cls) -> Iterable[Callable[..., Any]]:
            yield cls.validate

        @classmethod

    try:
        from pydantic_core.core_schema import (
            with_info_plain_validator_function as with_info_plain_validator_function,
        )
    except ImportError:  # pragma: no cover
        from pydantic_core.core_schema import (
            general_plain_validator_function as with_info_plain_validator_function,  # noqa: F401
        )

    Required = PydanticUndefined

    app = FastAPI()
    with pytest.raises(FastAPIError) as e:

        @app.get("/")
        def read_root() -> Union[Response, None]:
            return Response(content="Foo")  # pragma: no cover

    assert "valid Pydantic field type" in e.value.args[0]
    assert "parameter response_model=None" in e.value.args[0]


def test_openapi_schema():
    response = client.get("/openapi.json")