How can I use SafeDeleteQueryset and SafeDeleteManager at the same time?

[neoneo40]

# models.py

class BoardQuerySet(SafeDeleteQueryset):

    def is_public(self):
        return self.filter(is_public=True)

    def for_user(self, user):
        return self.filter(user=user)


class BoardManager(SafeDeleteManager):
    def get_queryset(self):
        return BoardQuerySet(self.model, self._db).select_related('user', 'board_category')

    def is_public(self):
        return self.get_queryset().is_public()

    def for_user(self, user):
        return self.get_queryset().for_user(user)
        
        
class Board(BaseBoard):
    pass

    objects = BoardManager()

In [4]: Board.deleted_objects.all().count()
Out[4]: 5

In [6]: Board.all_objects.all().count()
Out[6]: 6

In [8]: Board.objects.all().count()
Out[8]: 6

I don't understand why Board.objects.all().count() gets 6 instead of 1.
When you apply objects = SafeDeleteManager(), 1 is normally displayed.

The reason I did that is to call the function in a chainable manner.
Board.objects.is_public().for_user(user=user)
It's meant to be done this way, but it doesn't work.

Situations I've Experienced

1. If you do objects = BoardQuerySet.as_manager(), it works normally and 1 comes out. However, because select_related does not work, the number of queries increases from 10 to 20, so the speed decreases significantly.

2. objects = BoardManager.from_queryset(BoardQuerySet)()
   When BoardManager.from_queryset(BoardQuerySet)() is used, deleted objects are not visible, but many queries occur because select_related is not applied.

Of course, the simplest solution would be to use Board.objects.filter(delted__isnull=False), but this is not an advantage of using the Manager. Please let me know how to solve it.

TMP Solution

class BoardManager(SafeDeleteManager):
    def get_queryset(self):
        qs = BoardQuerySet(self.model, self._db).exclude(deleted__isnull=False).select_related('user', 'board_category')
        qs = qs.order_by('-pk')
        return qs

1. Available Board.objects.is_public().for_user(user=user)
2. correct working return 1