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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 _on_stream_update(self, data):
 """Handle stream update."""

        self._streams[data.get('id')].update(data.get('stream'))
        _LOGGER.info('stream %s updated', self._streams[data.get('id')].friendly_name)
        for group in self._groups.values():
            if group.stream == data.get('id'):
                group.callback()