docs: def after_rollback_listener(self, session):
          """
          Rollback of the transaction, undo the indexes.
          If our transaction is terminated, we will reset the
          indexing assignments.
          """
          log.info('Removing indexing orders.')
          try:
              session.index_new[self.cls_name].clear()
              session.index_dirty[self.cls_name].clear()
              session.index_deleted[self.cls_name].clear()
          except (AttributeError, KeyError):
              log.warning('Trying to remove indexing orders, but indexing sets are not present.')