This might be a good place to link out to some comparisons of Python 2.x vs 3.x, including the overlap. I'm new to both versions, which is why I'm shopping this tutorial, but I found this page helpful:

http://python-notes.curiousefficiency.org/en/latest/python3/questions_and_answers.html

In particular, the section on why it might now make sense to learn Python 3 first, and Python 2 as a follow-up, convinced me that I should probably follow that advice. So maybe I'll be back! But I'll probably head over to a different tutorial for the time being.