Function _del_attribute

lib/sqlalchemy/orm/decl_base.py:2156–2177

(cls: Type[Any], key: str)

def _del_attribute(cls: Type[Any], key: str) -> None:
    if (
        "__mapper__" in cls.__dict__
        and key in cls.__dict__
        and not cast(
            "MappedClassProtocol[Any]", cls
        ).__mapper__._dispose_called
    ):
        value = cls.__dict__[key]
        if isinstance(
            value, (Column, _MapsColumns, MapperProperty, QueryableAttribute)
        ):
            raise NotImplementedError(
                "Can't un-map individual mapped attributes on a mapped class."
            )
        else:
            type.__delattr__(cls, key)
            cast(
                "MappedClassProtocol[Any]", cls
            ).__mapper__._expire_memoizations()
    else:
        type.__delattr__(cls, key)


def _declarative_constructor(self: Any, **kwargs: Any) -> None: