Karthikeyan Singaravelan <tir.karthi@gmail.com> added the comment: Thanks for the report. You are correct. The parameters were introduced in issue21423 in 3.7. It seems that this backported by mistake with PR 10958 where minor grammar was fixed with 40a61da40d252626f8b9ff524d76c1f0ccb3a4f7 but backporting caused the whole paragraph to be added to 3.6. 3.6 is in security fixes only mode. So I am not sure about the fix being merged. I am adding Ned to take a call on this. ---------- nosy: +ned.deily, xtreak _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue36195> _______________________________________