Method _assert_none_str

lib/sqlalchemy/engine/url.py:234–240

(
        cls, v: Optional[str], paramname: str
    )

    @classmethod
    def _assert_none_str(
        cls, v: Optional[str], paramname: str
    ) -> Optional[str]:
        if v is None:
            return v

        return cls._assert_str(v, paramname)

    @classmethod
    def _str_dict(