code: async def check_authorized(self, identity):
          
          identify = await self.identify(identity)
          if identify is None:
              raise UnauthorizedError()
          return identify
docs: Works like :func:`Security.identity`, but when check is failed
          :func:`UnauthorizedError` exception is raised.
  
          :param identity: Claim
          :return: Checked claim or return ``None``
          :raise: :func:`UnauthorizedError`