prefetch_related for multiple Levels

Since Django 1.7, instances of django.db.models.Prefetch class can be used as an argument of .prefetch_related. Prefetch object constructor has a queryset argument that allows to specify nested multiple levels prefetches like that:

Project.objects.filter(
        is_main_section=True
    ).select_related(
        'project_group'
    ).prefetch_related(
        Prefetch(
            'project_group__project_set',
            queryset=Project.objects.prefetch_related(
                Prefetch(
                    'projectmember_set',
                    to_attr="projectmember_list"
                )
            ),
            to_attr="project_list"
        )
    )

It is stored into attributes with _list suffix because I use ListQuerySet to process prefetch results (filter / order).