old_contents: from django.core.management.base import BaseCommand
  from django.db import DEFAULT_DB_ALIAS
  
  from optparse import make_option
  
  
  class Command(BaseCommand):
  
      option_list = BaseCommand.option_list + (
          make_option('--connection',
                      action='store',
                      dest='connection',
                      default=DEFAULT_DB_ALIAS,
                      ),
      )
  
      def handle(self, *args, **options):
          from courriers.backends import get_backend
          from courriers.models import NewsletterSubscriber
  
          self.connection = options.get('connection')
  
          backend_klass = get_backend()
  
          backend = backend_klass()
  
          unsubscribed_users = (NewsletterSubscriber.objects.using(self.connection)
                                                            .filter(is_unsubscribed=True)
                                                            .values_list('email', flat=True)
                                                            .order_by('-unsubscribed_at'))
  
          mailjet_contacts = backend.mailjet_api.contact.list()
  
          mailjet_users = []
          for contact in mailjet_contacts['result']:
              mailjet_users.append(contact['email'])
  
          diff = list(set(unsubscribed_users) - set(mailjet_users))
  
          print "%d contacts to unsubscribe" % len(diff)
  
          for email in diff:
              backend.unregister(email)
  
              print "Unsubscribe user: %s" % email
  
new_contents: from django.core.management.base import BaseCommand
  from django.db import DEFAULT_DB_ALIAS
  
  from optparse import make_option
  
  
  class Command(BaseCommand):
  
      option_list = BaseCommand.option_list + (
          make_option('--connection',
                      action='store',
                      dest='connection',
                      default=DEFAULT_DB_ALIAS,
                      ),
      )
  
      def handle(self, *args, **options):
          from courriers.backends import get_backend
          from courriers.models import NewsletterSubscriber
  
          self.connection = options.get('connection')
  
          backend_klass = get_backend()
  
          backend = backend_klass()
  
          unsubscribed_users = (NewsletterSubscriber.objects.using(self.connection)
                                                            .filter(is_unsubscribed=True)
                                                            .values_list('email', flat=True)
                                                            .order_by('-unsubscribed_at'))
  
          mailjet_contacts = backend.mailjet_api.contact.list()
  
          mailjet_users = [contact['email'] for contact in mailjet_contacts['result']]
  
          diff = list(set(unsubscribed_users) - set(mailjet_users))
  
          print "%d contacts to unsubscribe" % len(diff)
  
          for email in diff:
              backend.unregister(email)
  
              print "Unsubscribe user: %s" % email
  
subject: Use list comprehension for mailjet_users list