title: How can I define custom output types for mutations with graphene-django?
body: <p>Create/remove/update/delete (CRUD) mutations usually return the corresponding database model instance as output type of the mutation. However for non-CRUD mutations I'd like to define business logic specific mutation output types. E.g. returning the count of list elements + a list of IDs which cannot be mapped 1-to-1 between graphql type and db models. How can I achieve this with <code>graphene-django</code>?</p>