docs: def get_relationships_for_destination(self, destination_id=None):
          """Gets a ``RelationshipList`` corresponding to the given peer ``Id``.
  
          arg:    destination_id (osid.id.Id): a peer ``Id``
          return: (osid.relationship.RelationshipList) - the relationships
          raise:  NullArgument - ``destination_id`` is ``null``
          raise:  OperationFailed - unable to complete request
          raise:  PermissionDenied - authorization failure
          *compliance: mandatory -- This method must be implemented.*
  
          """
          if destination_id is None:
              raise NullArgument()
          url_path = ('/handcar/services/relationship/families/' +
                      self._catalog_idstr + '/relationships?sourceid=' +
                      str(destination_id))
          return objects.RelationshipList(self._get_request(url_path))