def refresh(self, scope_list=None):
        """ Update the auth data (tokens) using the refresh token in auth.
        """
        request_data = self.get_refresh_token_params(scope_list)
        res = self._session.post(**request_data)
        if res.status_code != 200:
            raise APIException(
                request_data['url'],
                res.status_code,
                response=res.content,
                request_param=request_data,
                response_header=res.headers
            )
        json_res = res.json()
        self.update_token(json_res)
        return json_res