How do I make Python 3.5 my default version on MacOS?

Question

I have just installed Python 3.5.1 on my Mac (running the latest version of OSX). My system came with Python 2.7 installed. When I type IDLE at the Terminal pro

Answer 1

It's good practice to have your MacOS Python environment set up properly from the beginning making sure that Homebrew installations take precedence over stock MacOS binaries. You want it in usr/local/bin not MacOS default usr/bin.

.bash_profile

# Ensure user-installed binaries take precedence
export PATH=/usr/local/bin:$PATH
# Load .bashrc if it exists
test -f ~/.bashrc && source ~/.bashrc

Can also create aliases for both.

alias py2='python2.7'
alias py3='python3.6'

Source the file to ensure it takes effect for the current session

source ~/.bash_profile

Homebrew install and setup etc...

/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

brew doctor
brew update
brew upgrade --all
brew cleanup

Python3 install

brew install python3

Next

pip3 install virtualenv

Next

pip3 install virtualenvwrapper

When all is finished python3, pip3, virtualenv, and virtualenvwrapper.sh will all be in usr/local/bin.

Result

Every time I install anything or use commands like mkvirtualenv Python 3 is used by default.