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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 queryset(self, request):
 """ Exclude replies from listing since they are displayed inline as part of listing. For proxy models with cls apptribute limit comments to those classified as cls. """

        qs = super(CommentAdmin, self).queryset(request)
        qs = qs.filter(
            Q(user__is_staff=False) | Q(user__isnull=True),
            is_removed=False
        )
        cls = getattr(self, 'cls', None)
        if cls:
            qs = qs.filter(classifiedcomment__cls=self.cls)
        return qs.select_related('user', 'content_type')