docs: def is_expired(self, token, when=0):
          """
          Evaluate whether the token has expired or not
  
          :param token: The token
          :param when: The time against which to check the expiration
              0 means now.
          :return: True/False
          """
          verifier = JWT(key_jar=self.key_jar, allowed_sign_algs=[self.alg])
          _payload = verifier.unpack(token)
          return is_expired(_payload['exp'], when)