Method _update

lib/sqlalchemy/event/base.py:202–212

Populate from the listeners in another :class:`_Dispatch` object.

(
        self, other: _Dispatch[_ET], only_propagate: bool = True
    )

        return _UnpickleDispatch(), (self._instance_cls,)

    def _update(
        self, other: _Dispatch[_ET], only_propagate: bool = True
    ) -> None:
        """Populate from the listeners in another :class:`_Dispatch`
        object."""
        for ls in other._event_descriptors:
            if isinstance(ls, _EmptyListener):
                continue
            getattr(self, ls.name).for_modify(self)._update(
                ls, only_propagate=only_propagate
            )

    def _clear(self) -> None:
        for ls in self._event_descriptors: