A cache decorator with a ability of lossing memory .

cached.py

def cached(function):
    cache = {}
    def wrapper(*args):
        if args in cache:
            ret=cache[args]
            if random.randint(1,100)>95: memo.pop(args) # random forget something
            return ret
        else:
            result = function(*args)
            cache[args] = result 
            return result
    return wrapper