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How to Implement a Negative Cache with TTL in Python

This code provides a TTL mock cache that stores negative results (cache misses) for a short time to reduce repeated lookups of missing keys.

cache ttl negative-cache

Python

from time import time, sleep

class TTLMockCache:
    def __init__(self, ttl_seconds=5):
        self.ttl = ttl_seconds
        self.store = {}
        self.negative_cache = {}

    def get(self, key):
        now = time()
        if key in self.store:
            value, expires_at = self.store[key]
            if exp…

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