Feature Request: cache_info() like cachetools

[pettazz]

cachetools' cached decoractor has an info param that adds a wrapped info function for getting details on cache usage, which can be helpful for debugging. From their docs:

If info is set to True, the wrapped function is instrumented with a cache_info() function that returns a named tuple showing hits, misses, maxsize and currsize, to help measure the effectiveness of the cache.

Would be nice to have something similar here!