In python-dev mailing list, it was asked what to do when a PR will address multiple issues.
https://mail.python.org/archives/list/python-dev@python.org/thread/74FS2DW2L4MDJXRREAABXYRWNI6INMBA/

From few answers from the core devs, seems like we prefer keeping only one issue open (the oldest one), and mark the rest as duplicates. Also, our workflow (bots and blurb) kinda expects 1 bpo issue per 1 pull request.

It would be great to clarify all of the above in either thepull request life cycle page, or in thetriaging page.