In the Django documentation, it mentions that when you directly specify the new related set, any models no longer in the set are simply disassociated instead of deleted.
In other words, if you have a situation like this:
#author.books contains [book1, book2, book3]
author.books = [book1, book2]
author.save()
The book 3 model is no longer associated with the author, but it is NOT deleted. Is there a way to disassociate AND delete the model?