def logout_user(self, request, response):
        if self._cookie_name in request.cookies:
            response.delete_cookie(self._cookie_name)
            key = request.cookies[self._cookie_name]
            if key != None:
                if not self.storage.delete(self._cookie_name + ':' + \
                                                key.encode('utf-8')):
                    logger.warning('storage "%r" is unreachable', self.storage)
dataset/ETHPy150Open SmartTeleMax/iktomi/iktomi/auth.py/CookieAuth.logout_user/operator `is not` -> `!=`