old_contents: from django.test import TestCase
  from Instanssi.kompomaatti.models import Entry
  
  
  VALID_YOUTUBE_URLS = [
      # must handle various protocols in the video URL
      "http://www.youtube.com/v/asdf123456",
      "https://www.youtube.com/v/asdf123456/",
      "//www.youtube.com/v/asdf123456",
      "www.youtube.com/v/asdf123456",
      # must handle various other ways to define the video
      "www.youtube.com/watch?v=asdf123456",
      "http://youtu.be/asdf123456",
      "http://youtu.be/asdf123456/"
  ]
  
  
  class KompomaattiTests(TestCase):
      def setUp(self):
          pass
  
      def test_youtube_urls(self):
          """Test that various YouTube URLs are parsed properly."""
          for url in VALID_YOUTUBE_URLS:
              print("Test URL: %s" % url)
              self.assertEqual(Entry.youtube_url_to_id(url), "asdf123456")
  
new_contents: from django.test import TestCase
  from Instanssi.kompomaatti.models import Entry
  
  
  VALID_YOUTUBE_URLS = [
      # must handle various protocols and hostnames in the video URL
      "http://www.youtube.com/v/asdf123456",
      "https://www.youtube.com/v/asdf123456/",
      "//www.youtube.com/v/asdf123456",
      "www.youtube.com/v/asdf123456",
      "youtube.com/v/asdf123456/",
      # must handle various other ways to define the video
      "www.youtube.com/watch?v=asdf123456",
      "http://youtu.be/asdf123456",
      "https://youtu.be/asdf123456/"
  ]
  
  
  class KompomaattiTests(TestCase):
      def setUp(self):
          pass
  
      def test_youtube_urls(self):
          """Test YouTube video id extraction from URLs."""
          for url in VALID_YOUTUBE_URLS:
              self.assertEqual(Entry.youtube_url_to_id(url), "asdf123456",
                               msg="failing URL: %s" % url)
  
subject: Add more test data; improve feedback on failing case