@get_client()
    def ttl(self, client, key):
        if client.exists(key):
            return client.ttl(key)
        return 0
Get a sync for a client which is starting without any state.
dataset/ETHPy150Open sebleier/django-redis-cache/redis_cache/backends/base.py/BaseRedisCache.ttl--crossover with--dataset/ETHPy150Open matrix-org/synapse/synapse/handlers/sync.py/SyncHandler.full_state_sync