docs: def poll_crontab(self):
          """Check crontab and run target jobs
          """
          polled_time = self._get_current_time()
          if polled_time.second >= 30:
              self.log.debug('Skip cronjobs in {}'.format(polled_time))
              return
          for job in self._crontab:
              if not job.is_runnable(polled_time):
                  continue
              job.do_action(self, polled_time)