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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 refresh_token(self, headers=None, **kwargs):
 """ Request a refreshed token """

        self._check_configuration("site", "token_url", "client_id",
                                  "client_secret")
        url = "%s%s" % (self.site, quote(self.token_url))
        data = {
            'client_id': self.client_id,
            'client_secret': self.client_secret,
        }
        data.update(kwargs)

        return self._make_request(url, data=data, headers=headers)