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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 followers(request, content_type_id, object_id, flag):
 """ Creates a listing of ``User``s that follow the actor defined by ``content_type_id``, ``object_id``. """

    ctype = get_object_or_404(ContentType, pk=content_type_id)
    instance = get_object_or_404(ctype.model_class(), pk=object_id)
    flag = flag or ''

    return render(
        request,
        'actstream/followers.html',
        {
            'followers': models.followers(instance, flag=flag),
            'actor': instance,
        }
    )