Updating Python on Mac
The default Python on OS X shouldn't be messed with as it's used by the OS itself. If your default is 2.6.1 then you must have Snow Leopard.
If you just install from the standard 3.1 disk image then you can invoke it using python3.1 from the terminal (you don't have to do any extra steps for this to work) and you can leave the plain python as 2.6.1.
Both python 2x and 3x can stay installed in a MAC. Mac comes with python 2x version. To check the default python version in your MAC, open the terminal and type-
python --versionHowever to check, if you have already installed any of python 3x versions, you need to type
python3 --versionIf you don't then go ahead and install it with the installer. Go the the python's official site(https://www.python.org/downloads/), download the latest version
and install it.
Now restart the terminal and check again with both commands-
Hope this helps.
using Homebrew just do:
brew install python3 && cp /usr/local/bin/python3 /usr/local/bin/pythondone :)