code: def handle(self, *args, **options):
  		
  		qs = get_subscriber_model().objects.filter(djstripe_customers__isnull=True)
  		count = 0
  		total = qs.count()
  		for subscriber in qs:
  			count += 1
  			perc = int(round(100 * (float(count) / float(total))))
  			print(
  				"[{0}/{1} {2}%] Syncing {3} [{4}]".format(
  					count, total, perc, subscriber.email, subscriber.pk
  				)
  			)
  			sync_subscriber(subscriber)
docs: Call sync_subscriber on Subscribers without customers associated to them.