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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def find_behind_subscriptions():
 """ Finds any subscriptions that are behind according to where they should be, and creates a BehindSubscription entry for them. """

    subscriptions = Subscription.objects.filter(
        active=True, completed=False, process_status=0
    ).values_list("id", flat=True)
    for subscription_id in subscriptions.iterator():
        calculate_subscription_lifecycle.delay(str(subscription_id))