update python version mac code example

Example 1: mac upgrade python to 3.8

brew install python3
brew update && brew upgrade python
alias python=/usr/local/bin/python3

Example 2: how to set default python version in macos

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

Example 3: which python mac

$ brew update && brew upgrade python

Example 4: mac why is python installed in usr and application

$ pyenv global 3.7.3
# and verify it worked 
$ pyenv version
3.7.3 (set by /Users/mbbroberg/.pyenv/version)

Example 5: 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