code: def rollback(self):
          
          self._check_thread()
          if self.state not in (_STATE_ACTIVE, _STATE_PARTIAL_COMMIT):
              raise TransactionError("Transaction is not active.")
          try:
              if self.state != _STATE_PARTIAL_COMMIT:
                  request = transaction_rollback_codec.encode_request(self.id, self.thread_id)
                  self.client.invoker.invoke_on_connection(request, self.connection).result()
              self.state = _STATE_ROLLED_BACK
          finally:
              self._locals.transaction_exists = False
docs: Rollback of this current transaction.