What is the correct way to write an annotation?

Question

Django

There is a user model:

class Contact(AbstractBaseUser, PermissionsMixin):
    '''Кастомная модель пользователя'''
    email = models.EmailField(verbose_name='email', max_length = 60, unique = True)
    slug = models.SlugField(default='')
    first_name = models.CharField(max_length=30, default = '')
    last_name = models.CharField(max_length=30, default = '')
    phone_number = models.CharField(max_length=11)
    date_joined = models.DateTimeField(verbose_name='date joined', auto_now_add = True)
    last_login = models.DateTimeField(verbose_name='last login', auto_now = True)
    is_admin = models.BooleanField(default=False)
    is_staff = models.BooleanField(default=False)
    is_superuser = models.BooleanField(default=False)
    avatar = models.ImageField(upload_to='user_avatars/%Y/%m/%d', blank=True)
    compressed_avatar = models.ImageField(upload_to='compressed_user_avatars/%Y/%m/%d', blank=True)
    small_avatar = models.ImageField(upload_to='small_user_avatars/%Y/%m/%d', blank=True)
    is_active = models.BooleanField(default=False)

There is a photo model:

class Photo(models.Model):
    '''Фотография'''
    owner = models.ForeignKey(Page, related_name='photos', on_delete=models.CASCADE)
    picture = models.ImageField(upload_to='picture/%Y/%m/%d')
    compressed_picture = models.ImageField(upload_to='compressed_picture/%Y/%m/%d')
    small_picture = models.ImageField(upload_to='small_picture/%Y/%m/%d')
    likes = models.ManyToManyField(Like)
    comments = models.ManyToManyField(Comment)
    timestamp = models.DateTimeField(auto_now_add=True)

There is a detail-view on the Contact model and an overloaded get_queryset() in it:

def get_queryset(self):
         pk = int(self.kwargs['pk'])
        queryset = Contact.objects.filter(id=pk).annotate(
            is_friend=Count('my_page__friends', filter=Q(my_page__friends=self.request.user))
        ).annotate(
            num_friends=Count('my_page__friends', distinct=True)
        ).annotate(
            current_user=Count('slug', filter=Q(slug=self.request.user.slug))
        ).annotate(
            is_sent=Exists(
                AddRequest.objects.filter(
                    sender__id=self.request.user.id, 
                    receiver__id=pk
                )
            )
        ).annotate(
            is_sent_to_you=Exists(
                AddRequest.objects.filter(
                    sender__id=pk, 
                    receiver__id=self.request.user.id
                )
            )
        ).annotate(
            chat_id=Avg('chats__id', filter=Q(chats__participants=self.request.user))
        )
        return queryset

When displaying all this information about the user, I would very much like to display the ID of the current avatar, when I change the avatar, an entity of the Photo type is automatically created, where the addresses of the pictures are the same as on the avatar itself, which sits in the Contact model.
I tried to do something like this like this:

queryset = queryset.annotate(
                photo_id=Sum('my_page__photos__id', filter=Q(my_page__photos__picture=OuterRef('avatar')))
            )

As a result, I get 404, although the avatar field is not empty.

It is possible to make a crooked solution through a conditional statement, but it is not very efficient

. Thanks for any help!

(my_page is an entity that connects the user and some other entities, this is not so important, it is important that in this way you can get a list of his photos from the user; I just described it for a clearer understanding of the picture)