I am delete post in admin panel, put pk of new post equal 2, not 1. Why? What am i do wrong?
That's example of my model.
class Post(models.Model):
    author = models.ForeignKey('auth.User')
    category = models.ForeignKey(Categories)
    title = models.CharField(max_length=200,verbose_name='Заголовок')
    text = models.TextField(verbose_name='Текст')
    created_date = models.DateTimeField(verbose_name='Время создания',default=timezone.now)
    published_date = models.DateTimeField(verbose_name='Время публикации',blank=True, null=True)
    def publish(self):
        self.published_date = timezone.now()
        self.save()
    def approved_commentimages(self):
        return self.comments.filter(approved_comment=True)
    def __str__(self):
        return self.title
