Timed KV Cache

Implement a timed key-value cache. Design a data structure that supports the following operations: put(key: str, value: any, ttl: int): Store a key-value pair (key, value) where ttl is the time-to-live in seconds for the given key. get(key: str) -> any: Return the value associated with the key. If the key does not exist or has expired, return null. Constraints Keys and values are strings. ttl is a positive integer. Achieve a time complexity as close to O(1) as possible for each operation. Example cache = TimedKVCache() cache.put("apple", "fruit", 5) # Set key "apple" with value "fruit" to expire in 5 seconds cache.get("apple") # Returns "fruit" # Wait for 5 seconds cache.get("apple") # Returns null as "apple" has expired Example Input put apple fruit 5 get apple wait 5 get apple Output fruit null