Advanced Filtering (Q objects, lookups, annotations)

# from django.db.models import Q, Count, Avg, Sum

# Q objects — complex conditions
# OR: posts that are published OR by admin
# Post.objects.filter(Q(published=True) | Q(author__username='admin'))

# AND with OR: published AND (python OR django in title)
# Post.objects.filter(
#     Q(published=True) &
#     (Q(title__icontains='python') | Q(title__icontains='django'))
# )

# NOT: exclude draft posts
# Post.objects.filter(~Q(published=False))

# Complex lookups
# Post.objects.filter(
#     title__icontains='django',
#     created_at__year=2026,
#     views_count__gte=50,
#     category__name__in=['Python', 'Django'],
# )

# Annotations — add computed columns
# from django.db.models import Count
# categories = Category.objects.annotate(
#     post_count=Count('posts')
# )
# for cat in categories:
#     print(f"{cat.name}: {cat.post_count} posts")

# Authors with most posts
# User.objects.annotate(
#     num_posts=Count('posts')
# ).order_by('-num_posts')[:5]