Does this line assume now that the primary key of a model is called id?

In the past the ModelSerializer generated (In this case the primary key on the Order model is order_id):

order = PrimaryKeyRelatedField(read_only=True)

Now I get:

order = SlugRelatedField(read_only=True, slug_field='order_id')

The issue comes up in that if instead I use a HyperlinkedModelSerializer, I no longer get a hyperlink for that field.