我得到了这个代码：

providers: [
    ChangeNotifierProvider.value(
      value: Auth(),
    ),
    ChangeNotifierProxyProvider<Auth, Products>(
      builder: (ctx, auth, previousProducts) => Products(
        auth.token,
        auth.userId,
        previousProducts == null ? [] : previousProducts.items,
      ),
    ),
    ChangeNotifierProvider.value(
      value: Cart(),
    ),
    ChangeNotifierProxyProvider<Auth, Orders>(
      builder: (ctx, auth, previousOrders) => Orders(
        auth.token,
        auth.userId,
        previousOrders == null ? [] : previousOrders.orders,
      ),
    ),
  ],

但它似乎已被弃用，并在hangeNotifierProxyProvider行中出现以下错误：

The parameter 'create' is required.
The parameter 'update' is required.

我不知道如何升级这部分代码？