How to add API Product to Existing App without changing the Credentials like Consumer Key , Consumer Secret and Attributes .using REST API

[#1]

I have The Multiple Developer API Products , I wanted to Add multiple Product to a existing Developer App without changing the Consumer Details like Key, Secret and Attributes etc.

I wanted to use APigee's REST API request .

Iam using Python Script to update perform the POST Request .

Iam able to ADD new Developer App using the Python Script but not the able to update the Developer aPP with multiple API Product.