Django Admin: list_display() order by count of related object

Question

Imagine you have a model Person which can have N Book instances.

I want to display the number of books a person has in the django admin change-list view.

It is easy to display the number (write a custom method on PersonAdmin).

But I could not find a way to make it sortable by the number of books a person has.

I read the docs for list_display, but could not find an answer.

According to the docs a query expression could be used. Is it possible to solve it this way?

After applying the answer, this is what it looks like. In this case each instance has N log entries:

Answer 1

Override the get_queryset() method of model admin with the help of annoate() and order_by() methods. Then, define a callable function(book_count()) to return the value to the change-list page

from django.db.models.aggregates import Count

class PersonAdmin(admin.ModelAdmin):
    list_display = ('book_count', 'other_field')

    def get_queryset(self, request):
        qs = super().get_queryset(request)
        qs = qs.annotate(book_count=Count('book')).order_by('-book_count')
        return qs

    def book_count(self, person_instance):
        return person_instance.book_count

    book_count.admin_order_field = 'book_count'

Why I didn't add ordering ?

While we calling the super(), Django will throw exceptions