Multiple Python versions

Because one does not simply mess with MacOS default Python

Install Homebrew

Homebrew is a package manager for MacOS, must have CLI utility.

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

Install latest python

MacOS comes with a python version but you should install the latest stable version of python.

 brew install python

Install pip

Download the get-pip file

curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py

Now run this file to install pip

python get-pip.py

Change global default python to latest python

sudo ln -s -f /usr/local/bin/python3.9 /usr/local/bin/python

Install pyenv

pyenv makes it easy to install, manage, and switch between multiple Pythons versions.

brew install pyenv

Install multiple python versions in pyenv

pyenv install 3.9.4
pyenv install 2.7.16

Change default python in pyenv to latest and greatest

pyenv global 3.9.4

Running pyenv

pyenv versions
python -m venv venv
source ./venv/bin/activate
(venv) $ which python

To exit the virtual environment

deactivate

References

• https://opensource.com/article/19/6/python-virtual-environments-mac

• https://jacobian.org/2019/nov/11/python-environment-2020/