This discussion looks like there's no end in sight. Maybe the Steering Council should take a vote?
I've merged the PR reverting the behavior in 3.8 and am doing the same in the master branch.
The sheer volume of email this is generating shows that we're not ready to do this to our users.
Recall the nightmare caused by md5.py and sha.py DeprecationWarning's in 2.5... this would be similar.
We need owners of code to see the problems, not end users of other peoples code.
FWIW, lest people think I don't like this change and just pushed the revert buttons as a result, wrong. I agree with the ultimate SyntaxError and believe we should move the language there (it is better for long term code quality). But it needs to be done in a way that disrupts the right people in the process, not disrupting an exponentially higher number of users of other peoples code.
If the steering council does anything it should be deciding if we're still going to do this at all and, if so, planning how we do it without repeating past mistakes.
-gps