I've recently install Python 3.1, but Emacs still uses 2.6.5. I'm using Emacs version 22.2.1. I'm not sure which files to edit in order to make Emacs use Python 3.1 by default!
I'm using python-mode.el and pyemacs, if that helps...
Best, Georgina
See a previous discussion on this
In your .emacs file, following should do:
;; python 3
(setq python-python-command "python3")