'Override save method to update parent thread info and take care of
created and updated.'

def save(self, *args, **kwargs):

    new = (self.id is None)
    if (not new):
        self.updated = datetime.datetime.now()
    super(Post, self).save(*args, **kwargs)
    if new:
        self.thread.replies = (self.thread.post_set.count() - 1)
        self.thread.last_post = self
        self.thread.save()
        self.thread.forum.last_post = self
        self.thread.forum.save()
