// ENV: Mac OSX 10.14.2
// Follow step by step (Python3)
$ which python3
... return /Library/Frameworks/Python.framework/Versions/xxx
// cd into Versions folder
$ cd /Library/Frameworks/Python.framework/Versions
// remove v3.7
$ sudo rm -rf 3.7 Current
// in /usr/local/bin
$ rm -rf python3.7*
$ rm -rf pydoc3*
brew rm python3
pip install --upgrade pip