code: def mark(self):
          
          self.reliableListener.lastRun = extime.Time()
          BatchProcessingError(
              store=self.reliableListener.store,
              processor=self.reliableListener.processor,
              listener=self.reliableListener.listener,
              item=self.workUnit,
              error=self.failure.getErrorMessage())
docs: Mark the unit of work as failed in the database and update the listener
          so as to skip it next time.