How to correctly use interfaces

[freddiemixell]

I've been looking over a bunch of example repos that have implemented GraphQL api's using Ariadne and one thing that I can't figure out is the usage of interfaces. This is one of the repo's I've been looking at for reference while I build.

I have 2 questions:

1. Do you need to use Interface type resolvers, because I see that repo I listed above isn't?
2. If you do need the interface type resolver, how do you handle something like a response interface? For example:

interface BaseResponse {
    success: Boolean!
    errors: [String]
}

This above example doesn't map to an object in the model so how would I create a resolver for it?