Method union

lib/sqlalchemy/ext/associationproxy.py:1942–1943

(self, *s: Iterable[_S])

        return set(iter(self))

    def union(self, *s: Iterable[_S]) -> MutableSet[Union[_T, _S]]:
        return set(self).union(*s)

    def __or__(self, __s: AbstractSet[_S]) -> MutableSet[Union[_T, _S]]:
        if not collections._set_binops_check_strict(self, __s):