gistfile1.txt

from django.core.cache import cache
from django.db.models.signals import post_save
from django.dispatch import receiver

@register.simple_tag()
def last_items(num=10):
    last_items = cache.get('last_items')
    if not last_items:
        ads = Ad.objects.filter(status='actual').order_by('-created_date', '-id')[:num]
        last_items = render_to_string('blocks/inline/last_items.html', {'ads': ads})
        cache.set('last_items', last_items)
    return last_items

@receiver(post_save, sender=Ad)
def clear_last_items(sender, instance, created, *args, **kwargs):
    cache.delete('last_items')