code: def recruit(self, n=1):
          
          logger.info("Recruiting {} MTurk participants".format(n))
          if not self.config.get("auto_recruit"):
              logger.info("auto_recruit is False: recruitment suppressed")
              return
  
          hit_id = self.current_hit_id()
          if hit_id is None:
              logger.info("no HIT in progress: recruitment aborted")
              return
  
          try:
              return self.mturkservice.extend_hit(
                  hit_id, number=n, duration_hours=self.config.get("duration")
              )
          except MTurkServiceException as ex:
              logger.exception(str(ex))
docs: Recruit n new participants to an existing HIT