brew uninstall python
So, I ended up removing all python installations, and reinstalling things via Homebrew.
which python ---> /Library/Frameworks/Python.framework/Versions/2.7/bin/python Delete the entire Python.framework directory from /Library/Frameworks.
which python3 ---> /usr/local/bin/python3 Delete the entire python3 directory.
I was a bit nervous about the symlinks. I initially renamed the ones that were obviously going to cause me trouble. It turns out that was unnecessary. Instead, just use:
$ brew doctor
Warning: Broken symlinks were found. Remove them with 'brew prune':
/usr/local/bin/python-32
/usr/local/bin/python2-32
/usr/local/bin/python2.7-32
/usr/local/bin/python2_DNU
/usr/local/bin/python_DNU
/usr/local/bin/pythonw-32
/usr/local/bin/pythonw2-32
/usr/local/bin/pythonw2.7-32
So, brew prune (or brew cleanup --prune in newer versions of Homebrew) worked perfectly. It removed all of the above symlinks.
Reinstall python and python3 via homebrew. All done.
At no time did I touch the python installation located within the /System folder.
Oh, and to be clear. The answer to the original question is