code: def transfer(self, rights_assignment_data=None, *, from_user, to_user,
                   rights_assignment_format='jsonld'):
          
  
          rights_assignment = RightsAssignment.from_data(
              rights_assignment_data or {},
              plugin=self.plugin)
          transfer_payload = rights_assignment._to_format(
              data_format=rights_assignment_format)
          transfer_id = super().transfer(transfer_payload, from_user=from_user,
                                         to_user=to_user)
  
          rights_assignment.persist_id = transfer_id
          return rights_assignment
docs: Transfer this Right to another owner on the backing
          persistence layer.
  
          Args:
              rights_assignment_data (dict): Model data for the resulting
                  :class:`~.RightsAssignment`
              from_user (any, keyword): A user based on the model specified
                  by the persistence layer
              to_user (any, keyword): A user based on the model specified
                  by the persistence layer
              rights_assignment_format (str, keyword, optional): Data
                  format of the created entity; must be one of:
  
                      - 'jsonld' (default)
                      - 'json'
                      - 'ipld'
  
          Returns:
              :class:`~.RightsAssignment`: The RightsAssignment entity
              created from this transfer
  
          Raises:
              See :meth:`~.TransferrableEntity.transfer`