code: def transfer(self, transfer_payload=None, *, from_user, to_user):
          
  
          if self.persist_id is None:
              raise EntityNotYetPersistedError(('Entities cannot be transferred '
                                                'until they have been '
                                                'persisted'))
  
          return self.plugin.transfer(self.persist_id, transfer_payload,
                                      from_user=from_user, to_user=to_user)
docs: Transfer this entity to another owner on the backing
          persistence layer
  
          Args:
              transfer_payload (dict): Payload for the transfer
              from_user (any): A user based on the model specified by the
                  persistence layer
              to_user (any): A user based on the model specified by the
                  persistence layer
  
          Returns:
              str: Id of the resulting transfer action on the persistence
              layer
  
          Raises:
              :exc:`~.EntityNotYetPersistedError`: If the entity being
                  transferred is not associated with an id on the
                  persistence layer (:attr:`~Entity.persist_id`) yet
              :exc:`~.EntityNotFoundError`: If the entity could not be
                  found on the persistence layer
              :exc:`~.EntityTransferError`: If the entity fails to be
                  transferred on the persistence layer
              :exc:`~.PersistenceError`: If any other unhandled error
                  in the plugin occurred