text: import os
  
  from django.core.files import File
  from django.core.files.uploadedfile import UploadedFile
  
  from categories.models import Category
  from django.test import TestCase
  
  
  class TestCategoryThumbnail(TestCase):
  
      def test_thumbnail(self):
  
          file_name = 'test_image.jpg'
  
          with open(os.path.join(os.path.dirname(__file__), file_name), 'rb') as f:
              test_image = UploadedFile(File(f), content_type='image/jpeg')
              category = Category.objects.create(name='Test Category', slug='test-category', thumbnail=test_image)
              self.assertEqual(category.pk, 1)
              self.assertEqual(category.thumbnail_width, 640)
              self.assertEqual(category.thumbnail_height, 480)
  