How to create objects(like in JS) in AWS appsync resolvers?

Question

I am trying to create this scenario in my resolvers file:

let { data } = await context.client.post(
      `https://myendpoint.com/api?action=getUserApiKey&user=${user}&password=${password}&2faCode=${secondFactorToken}`,
    );

    var userData = {
      username: data.user.username,
      email: data.user.email,
      name: data.user.name,
      userId: data.user.userId,
      avatarUrl: data.user.avatarUrl,
    };
    var params = {
      key: data.apiKey,
      user: userData,
    };
    return params;

to this in my appsync resolvers:

#if($ctx.result.statusCode == 200)
    #set($userData={
      $username: $ctx.result.username,
      $email: $ctx.result.email,
      $name: $ctx.result.name,
      $userId: $ctx.result.userId,
      $avatarUrl: $ctx.result.avatarUrl,
    })
    
    #set($params = {
      $key: $ctx.result.apiKey,
      $user: $userData,
    })
    
    $util.toJson($params);
#else
    $utils.appendError($ctx.result.body, "$ctx.result.statusCode")
#end

What will be the right syntax to perform this in appsync?