title: Django celery register periodic task
body: <p>I'm using <strong>Celery 4.4</strong> with <strong>Django 2.2</strong></p>
  
  <p>I have to create a <strong>Periodic Task</strong>, I'm extending <strong>PeriodicTask</strong> ask as</p>
  
  <pre><code>
  from celery.schedules import crontab
  from celery.task import PeriodicTask
  
  class IncompleteOrderHandler(PeriodicTask):
      run_every = crontab(
          minute='*/{}'.format(getattr(settings, 'INCOMPLETE_ORDER_HANDLER_PULSE', 5))
      )
  
      def run(self, *args, **kwargs):
          # Task definition
          eligible_users, slot_begin, slot_end = self.get_users_in_last_slot()
          map(lambda user: self.process_user(user, slot_begin, slot_end), eligible_users)
  
  </code></pre>
  
  <p>Earlier to register the above task, I used to call</p>
  
  <pre><code>from celery.registry import tasks
  
  tasks.register(IncompleteOrderHandler)
  </code></pre>
  
  <p>But now there is no <code>registry</code> module in the <code>celery</code>. How can I register the above periodic task?</p>