FWIW, my opinion on making this kind of wholesale change has not changed: see the discussion in PR 7800.  I think the changes made there were not an improvement for all the reasons stated, primarily because this now requires people reading the code base to learn *two* different ways of doing the same thing since these changes only affect the tests and not the platform-conditional code in the standard library modules themselves (which are not and should not be changed). Also, this means that backports of fixes from 3.8 will be complicated.  Note there ware already some "translation" errors detected and fixed in the PR re-spin; how many others remain?