def _exists_unlocked(self, key):
        now = timeutils.utcnow_ts()
        try:
            timeout = self._cache[key][0]
            return not timeout or now <= timeout
        except KeyError:
            return False
dataset/ETHPy150Open openstack/neutron/neutron/openstack/common/cache/_backends/memory.py/MemoryBackend._exists_unlocked/original