= '{% url "content_order" %}';

  sortable('#module-contents', {
    forcePlaceholderSize: true,
    placeholderClass: 'placeholder'
  })[0].addEventListener('sortupdate', function(e) {

    contentOrder = {};
    var contents = document.querySelectorAll('#module-contents div');
    contents.forEach(function (content, index) {
      // update content index
      contentOrder[content.dataset.id] = index;
    });

    // add new order to the HTTP request options
    options['body'] = JSON.stringify(contentOrd