Does anyone know where I can get an official StoreKit 1 example code from Apple?

We wish to implement in-app purchase for our app, which is currently targeting 14.3

The latest StoreKit 2, is only available for iOS 15

We wish to study how should we implement such, by looking at official code example of StoreKit 1.

However, the current posted code at Apple site, is only available for StoreKit 2 - https://developer.apple.com/documentation/storekit/in-app_purchase/implementing_a_store_in_your_app_using_the_storekit_api

Does anyone have any idea, where can I get the official StoreKit 1 code example, from Apple?

Thanks.

Does anyone know where I can get an official StoreKit 1 example code from Apple?
 
 
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