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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 _execute_stage(self, index, stage, stop):
 """ Execute a pipeline stage. :param index: Stage index. :param stage: Stage object. """

        if stop.is_set():
            _LOGGER.info("Stopped pipeline on group %s", self._group)
            return
        _LOGGER.info(" -> Running stage '%s' on group %s", stage, self._group)
        if stage.name == 'on':
            self._group.on = True
        elif stage.name == 'off':
            self._group.on = False
        elif stage.name == 'hue':
            self._group.hue = stage.args[0]
        elif stage.name == 'saturation':
            self._group.saturation = stage.args[0]
        elif stage.name == 'color':
            self._group.color = Color(*stage.args)
        elif stage.name == 'brightness':
            self._group.brightness = stage.args[0]
        elif stage.name == 'temperature':
            self._group.temperature = stage.args[0]
        elif stage.name == 'transition':
            self._group.transition(*stage.args, **stage.kwargs)
        elif stage.name == 'white':
            self._group.white()
        elif stage.name == 'white_up':
            self._group.white_up()
        elif stage.name == 'white_down':
            self._group.white_down()
        elif stage.name == 'red_up':
            self._group.red_up()
        elif stage.name == 'red_down':
            self._group.red_down()
        elif stage.name == 'green_up':
            self._group.green_up()
        elif stage.name == 'green_down':
            self._group.green_down()
        elif stage.name == 'blue_up':
            self._group.blue_up()
        elif stage.name == 'blue_down':
            self._group.blue_down()
        elif stage.name == 'night_light':
            self._group.night_light()
        elif stage.name == 'flash':
            self._group.flash(**stage.kwargs)
        elif stage.name == 'repeat':
            self._repeat(index, stage, stop)
        elif stage.name == 'wait':
            time.sleep(*stage.args)
        elif stage.name == 'callback':
            stage.args[0](*stage.args[1:], **stage.kwargs)