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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 post_url(self):

 """
 Determine which page this post lives on within the topic
 and return link to anchor within that page
 """

        topic = self.topic
        topic_page = topic.post_set.filter(id__lt=self.id).count() / get_paginate_by() + 1
        return "{0}page{1}/#post-{2}".format(topic.get_short_url(), topic_page, self.id)