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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 Join(self, Id):
 """Joins with another call to form a conference. :Parameters: Id : int Call Id of the other call to join to the conference. :return: Conference object. :rtype: `Conference` """

        #self._Alter('JOIN_CONFERENCE', Id)
        reply = self._Owner._DoCommand('SET CALL %s JOIN_CONFERENCE %s' % (self.Id, Id),
            'CALL %s CONF_ID' % self.Id)
        return Conference(self._Owner, reply.split()[-1])