discount codes for apps or in-app purchases?

aside from the beta-test type of promo codes, is there any way to have "reduced price" promo codes that are used via the Redeem feature in the app store, for either full apps or in-app purchases (possibly subscriptions)?
The reduced priced promo could would have to be created as a new IAP on AppStore connect. It's easier this way as the redemption happens in-app -- check out how the company Flyshot does it

discount codes for apps or in-app purchases?
 
 
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