jobs = group([reset_device.s(topoid, dev_list[i],
              waittime_list[i], skipflag) for i in range(len(dev_list))]
              ).apply_async(expires=waittime, retry=True, retry_policy={
                                                    'max_retries': 3,
                                                    'interval_start': 0.5,
                                                    'interval_step': 0.2,
                                                    'interval_max': 0.2})
results = jobs.join_native(timeout=waittime + 600, propagate=True)

jobs = chord([reset_device.s(topoid, dev_list[i],
              waittime_list[i], skipflag) for i in range(len(dev_list))])(callback)

jobs = chord([reset_device.s(topoid, dev_list[i], waittime_list[i],
             skipflag).set(expires=datetime.now() + timedelta(seconds=waittime)).set(retry=True).set(retry_policy=retry_policy)
              for i in range(len(dev_list))])(callback)

jobs = chord([reset_device.subtask(args=(topoid, dev_list[i], waittime_list[i],skipflag),
              expires=datetime.now()+timedelta(seconds=waittime), retry=True, retry_policy=retry_policy)
             for i in range(len(dev_list))])(callback)