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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, arguments):
 """ Refresh a user's access token, using existing the refresh token previously received in the auth flow. """


        new_access_token = None

        auth = ExistAuth(self.client_id, self.client_secret)
        resp = auth.refresh_token(self.access_token)
        if auth.token:
            new_access_token = auth.token['access_token']
            print('OAuth token refreshed: %s' % new_access_token)
            self.write_config(new_access_token)
        else:
            print('ERROR: We were unable to refresh the OAuth token | %s' % json.dumps(resp))