docs: def get_relationships(self):
          """Gets all ``Relationships``.
  
          return: (osid.relationship.RelationshipList) - a list of
                  ``Relationships``
          raise:  OperationFailed - unable to complete request
          raise:  PermissionDenied - authorization failure
          *compliance: mandatory -- This method must be implemented.*
  
          """
          url_path = ('/handcar/services/relationship/families/' +
                      self._catalog_idstr + '/relationships')
          return objects.RelationshipList(self._get_request(url_path))