[3.9] gh-121277: Allow .. versionadded:: next in docs (GH-121278) by encukou · Pull Request #128117 · python/cpython

…-121278) (pythonGH-127867)

Make `versionchanged:: next`` expand to current (unreleased) version.

When a new CPython release is cut, the release manager will replace
all such occurences of "next" with the just-released version.
(See the issue for release-tools and devguide PRs.)

Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
(cherry picked from commit 7d24ea9)

pythongh-121277: Raise nice error on `next` as second argument to deprecated-removed (pythonGH-124623)

(cherry-picked from e349f73)

Updates for 3.9

(cherry-picked from 3.11: f0895aa)
(cherry-picked from 3.10: 8773554)

* Use version, not arguments directly