| 341 | return None |
| 342 | |
| 343 | def _only_full_mapper_zero(self, methname: str) -> Mapper[Any]: |
| 344 | if ( |
| 345 | len(self._raw_columns) != 1 |
| 346 | or "parententity" not in self._raw_columns[0]._annotations |
| 347 | or not self._raw_columns[0].is_selectable |
| 348 | ): |
| 349 | raise sa_exc.InvalidRequestError( |
| 350 | "%s() can only be used against " |
| 351 | "a single mapped class." % methname |
| 352 | ) |
| 353 | |
| 354 | return self._raw_columns[0]._annotations["parententity"] # type: ignore # noqa: E501 |
| 355 | |
| 356 | def _set_select_from( |
| 357 | self, obj: Iterable[_FromClauseArgument], set_base_alias: bool |