text: from django.db import models
   
  class Relation(models.Model):
      
      product1 = models.CharField(max_length=80, null=True, blank=True)
      product2 = models.CharField(max_length=80, null=True, blank=True)
      count = models.IntegerField(null=True, blank=True)
      created_at = models.DateTimeField(auto_now_add=True)
  
      def __str__(self):
          return '지정상품1: {} vs 지정상품2: {}: 카운트: {}'.format(self.product1, self.product2, self.count)
      
      class Meta:
          ordering =['-created_at']