That makes sense. Got any ideas on how I could use `serializePolymorphicType` to lookup the type here? https://github.com/toranb/ember-data-django-rest-adapter/blob/polymorphic-associations/src/serializer.js#L37.

Right now it's checking for `{ authorType: 'x', author: {.. }}`,
or `{author: { type: 'x' } }` or `{author: { authorType: 'x' } }`.  I could probably eliminate a good chunk of code if I just pull the key from a function, though. The serializePoly.. function seems to perform on a whole object, though, but all I need is the resulting key name: https://github.com/emberjs/data/blob/master/packages/ember-data/lib/serializers/rest_serializer.js#L770