change to another python version mac code example

Example 1: change the default python version mac

ln -s -f /usr/local/bin/python3.7 /usr/local/bin/python

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