在队列中使用相同的task_id创建的任务

Question

我正在使用Django-celery和Redis后端推送芹菜队列中的任务。我正在队列中使用相同的自定义task_id推送任务。文档说task_id是UUID，它应该是唯一的。但我能够在队列中添加多个具有相同task_id的任务。如果队列中已存在具有相同task_id的任务，则应该引发异常。

@task
def register_task(a, b):
    print a + b

@task
def deregister_task(a, b, c):
    print a + b + c

taskid=str(UUID(md5('test').hexdigest()))
register_task.apply_async(args=('hello', 'world'), task_id=taskid, countdown=60)
deregister_task.apply_async(args=('sample', 'hello', 'world'), task_id=taskid, countdown=60)
i = inspect()
i.scheduled()

{u'celery@Suyashs-MacBook-Pro.local': [{u'eta': u'2017-06-05T17:15:33.947002',
   u'priority': 6,
   u'request': {u'acknowledged': False,
    u'args': u"('sample', 'hello', 'world')",
    u'delivery_info': {u'exchange': u'celery',
     u'priority': 0,
     u'redelivered': None,
     u'routing_key': u'celery'},
    u'hostname': u'celery@Suyashs-MacBook-Pro.local',
    u'id': u'098f6bcd-4621-d373-cade-4e832627b4f6',
    u'kwargs': u'{}',
    u'name': u'flight.tasks.deregister_task',
    u'time_start': None,
    u'worker_pid': None}},
  {u'eta': u'2017-06-05T17:15:44.234537',
   u'priority': 6,
   u'request': {u'acknowledged': False,
    u'args': u"('hello', 'world')",
    u'delivery_info': {u'exchange': u'celery',
     u'priority': 0,
     u'redelivered': None,
     u'routing_key': u'celery'},
    u'hostname': u'celery@Suyashs-MacBook-Pro.local',
    u'id': u'098f6bcd-4621-d373-cade-4e832627b4f6',
    u'kwargs': u'{}',
    u'name': u'flight.tasks.register_task',
    u'time_start': None,
    u'worker_pid': None}}]}