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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_flair(self, subreddit, redditor, **params):
 """Return the flair for a user on the given subreddit. :param subreddit: Can be either a Subreddit object or the name of a subreddit. :param redditor: Can be either a Redditor object or the name of a redditor. :returns: None if the user doesn't exist, otherwise a dictionary containing the keys `flair_css_class`, `flair_text`, and `user`. """

        name = six.text_type(redditor)
        params.update(name=name)
        url = self.config['flairlist'].format(
            subreddit=six.text_type(subreddit))
        data = self.request_json(url, params=params)
        if not data['users'] or \
                data['users'][0]['user'].lower() != name.lower():
            return None
        return data['users'][0]