field.validate, response_content, {}, loc=("response",)
            )
        if isinstance(errors_, list):
            errors.extend(errors_)
        elif errors_:
            errors.append(errors_)
        if errors:
            raise ResponseValidationError(
                errors=_normalize_errors(errors), body=response_content
            )

        if hasattr(field, "serialize"):

        webhooks: Annotated[
            Optional[routing.APIRouter],
            Doc(
                """
                Add OpenAPI webhooks. This is similar to `callbacks` but it doesn't
                depend on specific *path operations*.

                It will be added to the generated OpenAPI (e.g. visible at `/docs`).

                **Note**: This is available since OpenAPI 3.1.0, FastAPI 0.99.0.