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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 comment_set(self):
 """ Get the comments that have been submitted for the chat """

        ct = ContentType.objects.get_for_model(self.__class__)
        qs = Comment.objects.filter(
            content_type=ct,
            object_pk=self.pk)
        qs = qs.exclude(is_removed=True)
        qs = qs.order_by('-submit_date')
        return qs