static get attributes() {
    return [
      ...super.attributes,
      attributes.COLLAPSE_ICON,
      attributes.DISABLED,
      attributes.EXPAND_ICON,
      attributes.EXPANDED,
      attributes.ICON,
      attributes.LABEL,
      attributes.SELECTABLE,
      attributes.TOGGLE_COLLAPSE_ICON,
      attributes.TOGGLE_EXPAND_ICON,
      attributes.TOGGLE_ICON_ROTATE,
      attributes.USE_TOGGLE_TARGET
    ];
  }
/**
   * Return the attributes we handle as getters/setters
   * @returns {Array} The attributes in an array
   */
Return the attributes we handle as getters/setters
@returns {Array} The attributes in an array
Return the attributes we handle as getters / setters @returns { Array } The attributes in an array
static get attributes() {
    return [
      ...super.attributes,
      attributes.COLLAPSE_ICON,
      attributes.DISABLED,
      attributes.EXPAND_ICON,
      attributes.EXPANDED,
      attributes.ICON,
      attributes.LABEL,
      attributes.SELECTABLE,
      attributes.TOGGLE_COLLAPSE_ICON,
      attributes.TOGGLE_EXPAND_ICON,
      attributes.TOGGLE_ICON_ROTATE,
      attributes.USE_TOGGLE_TARGET
    ];
  }
static get attributes ( ) { return [ ... super . attributes , attributes . COLLAPSE_ICON , attributes . DISABLED , attributes . EXPAND_ICON , attributes . EXPANDED , attributes . ICON , attributes . LABEL , attributes . SELECTABLE , attributes . TOGGLE_COLLAPSE_ICON , attributes . TOGGLE_EXPAND_ICON , attributes . TOGGLE_ICON_ROTATE , attributes . USE_TOGGLE_TARGET ] ; }
Return the attributes we handle as getters/setters
 @returns {Array} The attributes in an array
Return the attributes we handle as getters / setters @returns { Array } The attributes in an array