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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 set_stream(self, stream_id):
 """Set group stream."""

        self._group['stream_id'] = stream_id
        yield from self._server.group_stream(self.identifier, stream_id)
        _LOGGER.info('set stream to %s on %s', stream_id, self.friendly_name)