@codebrainz approved this pull request.
Not tested but looks correct to use `py.exe`, having examined a default Windows installation.
I don't think it matters so much (for the default) about weird behaviour of `py.exe` with Python2 on Windows since anyone going forward who will be installing a dead/unsupported version is going to probably know enough to figure out how to customize the filetype/build-commands to use their special Python2 installation.