So what I'm gathering is that Martin fixed a bug that accidentally introduced a new one in 3.5.2 (which Martin should not feel responsible for; this import stuff is all very subtle and people use every nuance of it). To me, the question is whether there is a way to not revert Martin's fix -- or any other fixes -- while fixing Wolfgang's problem.

If the answer is yes, then great and we just need to know what the answer is in the form of a patch. :) My hope is someone will be inspired enough to figure out a solution and we can fix this for Wolfgang.

But if the answer is no, then we need to decide what the lesser of two bugs are. For me, I see Wolfgang's issue is the lesser of two bugs and thus the one that stays broken if we can't fix it reasonably (sorry, Wolfgang). Because we are trying to eliminate the double-import as that causes serious problems for anyone using import side-effects, I don't want to suddenly slide backwards in 3.5.3 by letting that happen again (and I think Nick agrees w/ me on that point). I also don't want people continuing down a path where they think that they can blank out critical import metadata and have import continue to work (not that I'm blaming Wolfgang for relying on it, just that it won't hold in the future). And since the reliance on __spec__ is just going to grow thanks to the elimination of double imports and slowly making that attribute the ground truth for import metadata, Wolfgang's code would need to be updated for Python 3.6 or later anyway.

But as I said, I'm sure everyone's utmost preference is if someone can figure out how to fix this in 3.5.3 without undoing another fix.