How should django-shop be configured through environment variables?

Question

Django

Decided to look at django-shop ( https://github.com/awesto/django-shop). The attached example uses configuration via environment variables ( https://github.com/awesto/django-shop/blob/master/...
It is clear that you can directly set environment variables and use it, but there is probably a more technological way to install environment variables and probably even implied in this project
How should these variables be set?