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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 async_add_scenes(self, scenes, async_set_state_callback):
 """Add scenes belonging to group."""

        self._scenes = {
            scene['id']: DeconzScene(self, scene, async_set_state_callback)
            for scene in scenes
            if scene['id'] not in self._scenes
        }