code: def run_check(participants, config, reference_time):
      
      recruiters_with_late_participants = defaultdict(list)
      for p in participants:
          timeline = ParticipationTime(p, reference_time, config)
          if timeline.is_overdue:
              print(
                  "Error: participant {} with status {} has been playing for too "
                  "long - their recruiter will be notified.".format(p.id, p.status)
              )
              recruiters_with_late_participants[p.recruiter_id].append(p)
  
      for recruiter_id, participants in recruiters_with_late_participants.items():
          recruiter = recruiters.by_name(recruiter_id)
          recruiter.notify_duration_exceeded(participants, reference_time)
docs: For each participant, if they've been active for longer than the
      experiment duration + 2 minutes, we take action.