TTLCache.expire() returns None instead of expired (key, value) pairs

TTLCache.expire() returns None instead of expired (key, value) pairs: a task in Repo2RLEnv R2E-Gym / SWEGEN (Harbor dataset). Calling TTLCache.expire() currently returns None , but it should return an iterable of (key, value) pairs for all items that were removed from the cache during the call.