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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_app_ticket(self, app_id):
 """Get app ownership ticket :param app_id: app id :type app_id: :class:`int` :return: `CMsgClientGetAppOwnershipTicketResponse <https://github.com/ValvePython/steam/blob/39627fe883feeed2206016bacd92cf0e4580ead6/protobufs/steammessages_clientserver.proto#L158-L162>`_ :rtype: proto message """

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