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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 add_phone_number(self, phone_number):
 """Add phone number to account Then confirm it via :meth:`confirm_phone_number()` :param phone_number: phone number with country code :type phone_number: :class:`str` :return: success (returns ``False`` on request fail/timeout) :rtype: :class:`bool` """

        sess = self._get_web_session()

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

        return (resp or {}).get('success', False)