python 3.x – Uninstalling python3 on MacOs
python 3.x – Uninstalling python3 on MacOs
Catalina comes with python3 installed by default**. You cant delete it, because /usr/bin is on the Systems read-only volume.
If you install your new python to a bin folder that comes before /usr/bin in your $PATH, then it should take precedence.
** (Well OK, the first time you run it, you have to install Xcode command line tools to make it work. But that file itself is a system install.)