Return the json dictionary containing traffic stats for a subreddit.

        :param subreddit: The subreddit whose /about/traffic page we will
            collect.

def get_traffic(self, subreddit):
        """Return the json dictionary containing traffic stats for a subreddit.

        :param subreddit: The subreddit whose /about/traffic page we will
            collect.

        """
        url = self.config['subreddit_traffic'].format(
            subreddit=six.text_type(subreddit))
        return self.request_json(url)