This is a python based implementation of PayPay's SDK. For the demonstration purpose we have used a simple Flask server with polling library to create QR code link and to check the order status of a QR code

$ cd server/python
$ pip install -r requirements.txt

$ export API_KEY="REPLACE_WITH_YOUR_API_KEY"
$ export API_SECRET="REPLACE_WITH_YOUR_SECRET_KEY" 
$ export MERCHANT_ID="REPLACE_WITH_YOUR_MERCHANT_ID" 

$ flask run

You should now have the API server running on http://localhost:5000

Additionally to trying out this application locally, you can deploy it to a variety of host services.