[anyfoo]

Ok, file handles are often good matches, unless you start allowing for them being changed outside of the file object, e.g. being closed or their position pointer modified (by e.g. seeking or reading).

So my example might not have been the best, because usually, they have a closely matching lifecycle, but the greater point that I was trying to make is that managing handles of handles (of handles) is not weird if you have to do some impedance matching. Maybe file handles are often straightforward, and therefore only require one "additional layer of handle indirection", but there's probably other good examples like say, threads in thread pools, or a whole bunch of stuff that's going on inside an OS kernel, especially a multiprocessing one.