the generated OpenAPI. Have in mind that this is a hack. But if you
                avoid using features added in OpenAPI 3.1.0, it might work for your
                use case.

                This is not passed as a parameter to the `FastAPI` class to avoid
                giving the false idea that FastAPI would generate a different OpenAPI
                schema. It is only available as an attribute.

                **Example**

            # that doesn't have the hashed_password. But because it's a subclass, it
            # would pass the validation and be returned as is.
            # By being a new field, no inheritance will be passed as is. A new model
            # will always be created.
            # TODO: remove when deprecating Pydantic v1
            self.secure_cloned_response_field: Optional[
                ModelField