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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 _to_edit_kind(self, post_uid):
        '''
        Show the page for changing the category.
        '''
        if self.userinfo and self.userinfo.role[1] >= '3':
            pass
        else:
            self.redirect('/')
        postinfo = MPost.get_by_uid(post_uid, )
        json_cnt = json.dumps(postinfo.extinfo, indent=True)
        kwd = {}
        self.render('man_info/post_kind.html',
                    postinfo=postinfo,
                    sig_dic=router_post,
                    userinfo=self.userinfo,
                    json_cnt=json_cnt,
                    kwd=kwd)