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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 get_cdn_auth_token(self, app_id, hostname):
 """Get CDN authentication token :param app_id: app id :type app_id: :class:`int` :param hostname: cdn hostname :type hostname: :class:`str` :return: `CMsgClientGetCDNAuthTokenResponse <https://github.com/ValvePython/steam/blob/39627fe883feeed2206016bacd92cf0e4580ead6/protobufs/steammessages_clientserver_2.proto#L585-L589>`_ :rtype: proto message """

        return self.send_job_and_wait(MsgProto(EMsg.ClientGetCDNAuthToken),
                                      {
                                       'app_id': app_id,
                                       'host_name': hostname,
                                      },
                                      timeout=15
                                     )