<course>
  <chapter url_name="Overview">
    <videosequence url_name="Toy_Videos">
      <html url_name="secret:toylab"/>
      <video url_name="Video_Resources" youtube="1.0:1bK-WdDi6Qw"/>
    </videosequence>
    <video url_name="Welcome" youtube="1.0:p2Q6BrNhdh8"/>
    <video url_name="video_123456789012" youtube="1.0:p2Q6BrNhdh8"/>
    <video url_name="video_123456789012" youtube="1.0:p2Q6BrNhdh8"/>
  </chapter>
  <chapter url_name="secret:magic"/>
</course>
