docs: function(group) {
              var groupName = $(group).prop('label');
  
              // Add a header for the group.
              var $li = $(this.options.templates.liGroup);
              $('label', $li).text(groupName);
  
              this.$ul.append($li);
  
              if ($(group).is(':disabled')) {
                  $li.addClass('disabled');
              }
  
              // Add the options of the group.
              $('option', group).each($.proxy(function(index, element) {
                  this.createOptionValue(element);
              }, this));
          }