text: 
  from io import BytesIO
  from PIL import Image
  
  
  from django.core.files import File
  from django.db import models
  
  from vendor.models import Vendor
  
  class Category(models.Model):
      title = models.CharField(max_length=255)
      slug = models.SlugField(max_length=255)
      ordering = models.IntegerField(default=0)
  
      class Meta:
          ordering = ['ordering']
      
      def __str__(self):
          return self.title
  
  class Product(models.Model):
      category = models.ForeignKey(Category, related_name='products', on_delete=models.CASCADE)
      vendor = models.ForeignKey(Vendor, related_name='products', on_delete=models.CASCADE)
      title = models.CharField(max_length=255)
      slug = models.SlugField(max_length=255)
      description = models.TextField(blank=True, null=True)
      price = models.DecimalField(max_digits=6, decimal_places=2)
      date_added = models.DateTimeField(auto_now_add=True)
      image = models.ImageField(upload_to='uploads/', blank=True, null=True)
      thumbnail = models.ImageField(upload_to='uploads/', blank=True, null=True)
  
      class Meta:
          ordering = ['-date_added']
      
      def __str__(self):
          return self.title
      
      def get_thumbnail(self):
          if self.thumbnail:
              return self.thumbnail.url
          else:
              if self.image:
                  self.thumbnail = self.make_thumbnail(self.image)
                  self.save()
  
                  return self.thumbnail.url
              else:
                  return 'https://via.placeholder.com/240x180.jpg'
      
      def make_thumbnail(self, image, size=(300, 200)):
          img = Image.open(image)
          img.convert('RGB')
          img.thumbnail(size)
  
          thumb_io = BytesIO()
          img.save(thumb_io, 'JPEG', quality=85)
  
          thumbnail = File(thumb_io, name=image.name)
  
          return thumbnail