how to change python version mac code example
Example 1: change default python version mac
$ brew install pyenv
$ pyenv install 3.7.3
$ pyenv global 3.7.3
$ pyenv version
3.7.3 (set by /Users/mbbroberg/.pyenv/version)
$ echo -e 'if command -v pyenv 1>/dev/null 2>&1; then\n eval "$(pyenv init -)"\nfi' >> ~/.bash_profile
$ exec $0
$ which python
$ python -V
$ pip -V
Example 2: how to change mac default python version
$ echo -e 'if command -v pyenv 1>/dev/null 2>&1; then\n eval "$(pyenv init -)"\nfi' >> ~/.zshrc