title: Celery - Obtain the Task ID in task_success signal?
body: <p>I have an application that implements the <code>task_success</code> signal like this:</p>
  
  <pre><code>@signals.task_success.connect
  def task_success_handler(sender=None,result=None,**kwargs):
      print("**************************C100")
      pprint.pprint(sender.name)
      print("**************************C100")
  </code></pre>
  
  <p>I can obtain the task name. Is there any way to obtain the <code>task_id</code>?</p>