How to use the @embroider/core.AppBuilder function in @embroider/core

let instantiate = async (root: string, appSrcDir: string, packageCache: PackageCache) => {
    let appPackage = packageCache.getApp(appSrcDir);
    let adapter = new CompatAppAdapter(
      root,
      appPackage,
      options,
      oldPackage,
      configTree,
      packageCache.get(join(root, 'node_modules', '@embroider', 'synthesized-vendor')),
      packageCache.get(join(root, 'node_modules', '@embroider', 'synthesized-styles'))
    );

    return new AppBuilder(root, appPackage, adapter, options);
  };