Is it possible to import a type from a prisma generated graphql file and then modify a field of it?

From what I've been doing - I've had to copy the entire type into my own typeDefs and then make the modification.

I was hoping I'd be able to maybe inherit and then override

We know about this. You can have a look into the future here that we will solve this: https://github.com/prisma/nexus-prisma

Exciting