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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_scenemode(self, scenemode='auto'):
 """Set the video scene mode. Return a coroutine. """

        if scenemode not in self.available_settings['scenemode']:
            _LOGGER.debug('%s is not a valid scenemode', scenemode)
            return False
        return self.change_setting('scenemode', scenemode)