Simplifying python2 vs python3 problems

In Arch Linux, python3 is default, so python2 programs have to be started manually, e.g. "python2 prog.py"

But sometimes that isn't enough either, so I found "virtualenv" which allows you to configure individual folders to work with an arbitrary python version.

First you configure the folder:

virtualenv -p python2 ~/myfolder/

Then before you run anything in that folder, you must source the generated script:

$ cd ~/myfolder/
$ source bin/activate
$ ./some_python_app