# 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
            ] = create_cloned_field(self.response_field)
        else:
            self.response_field = None  # type: ignore

            """
            'Whitelist' validation step. The parameter field will be the single one
            allowed by the alias or set of aliases defined.
            """
        ),
    ] = None,
    serialization_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Blacklist' validation step. The vanilla parameter field will be the

    grant_type: the OAuth2 spec says it is required and MUST be the fixed string "password".
        This dependency is strict about it. If you want to be permissive, use instead the
        OAuth2PasswordRequestForm dependency class.
    username: username string. The OAuth2 spec requires the exact field name "username".
    password: password string. The OAuth2 spec requires the exact field name "password".