code: def _decrypt(self, rj, token):
          
          if self.iss:
              keys = self.key_jar.get_jwt_decrypt_keys(rj.jwt, aud=self.iss)
          else:
              keys = self.key_jar.get_jwt_decrypt_keys(rj.jwt)
          return rj.decrypt(token, keys=keys)
docs: Decrypt an encrypted JsonWebToken
  
          :param rj: :py:class:`cryptojwt.jwe.JWE` instance
          :param token: The encrypted JsonWebToken
          :return: