mac change python3 version 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: set python3 as default mac
# it is said not to do but I used it anyway, because of the conveniency
$ echo "alias python=/usr/local/bin/python3.7" >> ~/.zshrc