You do realise that repo has last been updated 5 years ago. Don't expect everything to work - APIs change, Shopify moved along and that sample app is most definitely outdated. You'll be on your own figuring out why and how to get it up and running again though it may be easier to start from scratch.
The Shopify Python API wrapper seem to be active and maintained by same Shopify staff who are maintaining the de-facto reference Ruby wrapper. And a quick look around github shows a few more libs or demos that are quite recent.
If you feel more comfortable around Python then why bother with node.js and React? Not that I want to discourage you either way - I just find the languages and frameworks we use are more or less insignificant if we compare them side by side. What counts is what language and framework we are most productive with as individuals or a team. Also, you will eventually get stuck in either one - I always prefer to be stuck in a mess I understand than one I don't :-D
I was able to get it runing using the instructions in their README file here: https://github.com/Shopify/shopify_django_app.
At the time of this writing, the Git repo was updated 18 days earlier, so it seems like support for Django / Python has been improved.