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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 get_mood(self, mood_id, *, mood_parent=None):
 """ Return a mood. Returns a Command. """

        if mood_parent is None:
            mood_parent = self._get_mood_parent()

        def process_result(result):
            return Mood(result, mood_parent)

        return Command('get', [ROOT_MOODS, mood_parent, mood_id],
                       mood_parent, process_result=process_result)