My concern was that it seemed like at least one user had run into this while running 3.7.1rc1 (?), if I understood your comment; if so, I think we should mention in the changelog that the problem was fixed in rc2.

In any case, the state of the code for any release is captured as a git tag as described in the devguide.  As always, when switching versions, it's important to start with a clean build directory (make distclean or git clean -fdxq may help).

git checkout v3.7.0

https://devguide.python.org/devcycle/#development-cycle