def _add_reverse_property(self, key):
        other = self.mapper.get_property(key, _configure_mappers=False)
        self._reverse_property.add(other)
        other._reverse_property.add(self)

        if not other.mapper.common_parent(self.parent):
            raise sa_exc.ArgumentError(
                'reverse_property %r on '
                'relationship %s references relationship %s, which '
                'does not reference mapper %s' %
                (key, self, other, self.parent))

        if (ONETOMANY, MANYTOONE) in self.direction and self.direction \
                == other.direction:
            raise sa_exc.ArgumentError(
                '%s and back-reference %s are '
                'both of the same direction %r.  Did you mean to '
                'set remote_side on the many-to-one side ?' %
                (other, self, self.direction))
dataset/ETHPy150Open goFrendiAsgard/kokoropy/kokoropy/packages/sqlalchemy/orm/relationships.py/RelationshipProperty._add_reverse_property/swapped operands of `in`