I was not affected by Py3 at all. First I completely ignored it for five years while it gestated. Then started kicking the tires when 3.4 dropped on a LTS. When 3.6 with better dicts and f-strings landed I moved over with barely a whimper, since I'd had a decade to get things upgraded to 2.7 first.

None of my projects needed to worry much about char encoding, and I'd used logging extensively starting under 2.6 or so.