def test_backref_pop_m2o(self):
        User, Address = self.classes.User, self.classes.Address

        u1 = User()
        u2 = User()
        a1 = Address()
        u1.addresses.append(a1)
        u2.addresses.append(a1)

        # a1 removed from u1.addresses as of [ticket:2789]
        assert a1 not in u1.addresses

        assert a1.user is u2
        assert a1 in u2.addresses
dataset/ETHPy150Open zzzeek/sqlalchemy/test/orm/test_backref_mutations.py/O2MStaleBackrefTest.test_backref_pop_m2o/original