async def check_authorized(self, identity):
        """
        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`
        """
        identify = await self.identify(identity)
        if identify is None:
            raise UnauthorizedError()
        return identify