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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 clear_all_flair(self):
 """Remove all user flair on this subreddit. :returns: The json response from the server when there is flair to clear, otherwise returns None. """

        csv = [{'user': x['user']} for x in self.get_flair_list(limit=None)]
        if csv:
            return self.set_flair_csv(csv)
        else:
            return