Emacs 24.3.1 chose python version - missing variable?

Question

I have different versions of python (2.7 and 3) installed on my Linux Mint. Emacs by default (at least in my case) selects the old version.

How can I choose a newer one?

Attempting to change the following variable (as suggested here: https : //stackoverflow.com/a/165478/... or here: https://stackoverflow.com/a/164778/ ) does not work, since it is missing ?! [I do not know why...]

(setq python-python-command "python3")

with this it is the same (found here: http://www.bnikolic.co.uk/blog/python-running-emacs.html ):

(setq py-python-command "/usr/local/bin/python3")

Any suggestions? Thanks in advance.

Answer 1

, python.el:

python-shell-interpreter python3