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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 mark_topics_read(self, request, pk):
 """ Marks forum topics as read. """

        track_handler.mark_forums_read([self.forum, ], request.user)
        messages.success(request, self.success_message)
        return HttpResponseRedirect(self.get_forum_url())