Django receipts is a library for Django to verify receipts against a marketplace. An example is the Mozilla Marketplace. This library is optional.
Although this site will validate receipts, it should only be used as a test, not for your real apps.
curl -X POST http://django-receipts.herokuapp.com/receipts/receive --data "eyJhbGciOiAi...."
{"status": "error"}
Note: in this example the receipt fails because it has been truncated. Real ones pass, honest.
pip install django-receipts
Then read the docs.
For extra bonus points, you might want to look at the receipts that have been installed by the Mozilla Marketplace. For that, try receipts, a dependency of this.