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kotlinlang

e.g. ```class BasePerson : Person
Interface Person```?

If there's nothing more differentiating about your implementation that you can't choose a name for it, generally that means it's not necessary to have an interface.  If you're intending for other people to provide their own implementation, I've seen `DefaultPerson` used more in this scenario.  I feel like `BasePerson` is a better name for an abstract class, as you're expecting people to extend it.