In iOS 10, the concept of CoreData with Swift 3 has been changed by Apple. Despite the documentation, hands-on projects are a better explanation of changes in most cases and show how to implement them in own projects.
This example is a simple listing app in which you can add items and subsequently remove them when they are no longer needed.
What's New in Core Data in macOS 10.12, iOS 10.0, tvOS 10.0, and watchOS 3.0