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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 has_phone_number(self):
 """Check whether the account has a verified phone number :return: result :rtype: :class:`bool` or :class:`None` .. note:: Retruns `None` if the web requests fails for any reason """

        sess = self._get_web_session()

        try:
            resp = sess.post('https://steamcommunity.com/steamguard/phoneajax',
                            data={
                                'op': 'has_phone',
                                'arg': '0',
                                'checkfortos': 0,
                                'skipvoip': 1,
                                'sessionid': sess.cookies.get('sessionid', domain='steamcommunity.com'),
                                },
                            timeout=15).json()
        except:
            raise

        if resp['success'] == True:
            return resp['has_phone']