code: def requeue(self):
          
          timestamp = str(generate_epoch())
          # get all queue_types and requeue one by one.
          # not recommended to do this entire process
          # in lua as it might take long and block other
          # enqueues and dequeues.
          active_queue_type_list = self._r.smembers(
              '%s:active:queue_type' % self._key_prefix)
          for queue_type in active_queue_type_list:
              # requeue all expired jobs in all queue types.
              keys = [
                  self._key_prefix,
                  queue_type
              ]
  
              args = [
                  timestamp
              ]
              job_discard_list = self._lua_requeue(keys=keys, args=args)
              # discard the jobs if any
              for job in job_discard_list:
                  queue_id, job_id = job.split(':')
                  # explicitly finishing a job
                  # is nothing but discard.
                  self.finish(
                      job_id=job_id,
                      queue_id=queue_id,
                      queue_type=queue_type
                  )
docs: Re-queues any expired job (one which does not get an expire
          before the job_expiry_interval) back into their respective queue.
          This function has to be run at specified intervals to ensure the
          expired jobs are re-queued back.