Get light sensitivity value in iOS without private API?

I need to get a specific value from a sensor in lux . Therefore, other alternative methods such as screen brightness are not suitable for me.

IOKit seems to contain everything I need, but it's a private API and I won't be able to publish my app to the app store.

So are there any Apple-approved ways to get light sensor data? Or could you provide a link to the official Apple documentation / official forum discussion where it is described that you can only get light value through a private API?