Good question. It's a long road to Python 3, but it's a little easier to navigate now with the release of caniusepython3.
This script takes in a set of dependencies and then figures out which of them are holding you up from porting to Python 3.
It's a simple script which makes it just a little easier to use Python 3.
The output of the script will tell you how many (implicit) dependencies you need to transition to Python 3 in order to allow you to make the same transition. It will also list what projects have no explicit dependency blocking their transition so you can ask them consider starting a port to Python 3.