def conference(self, id, **options):
        """
        This object allows multiple lines in separate sessions to be conferenced together so that the parties on each line can talk to each other simultaneously.
        This is a voice channel only feature.
        Argument: "id" is a String
        Argument: **options is a set of optional keyword arguments.
        See https://www.tropo.com/docs/webapi/conference
        """
        self._steps.append(Conference(id, **options).obj)