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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 _fast_permalink(self):
 """Return the short permalink to the comment."""

        if hasattr(self, 'link_id'):  # from /r or /u comments page
            sid = self.link_id.split('_')[1]
        else:  # from user's /message page
            sid = self.context.split('/')[4]
        return urljoin(self.reddit_session.config['comments'], '{0}/_/{1}'
                       .format(sid, self.id))