The Writer is not a concrete class. Any object that implements write(), end(), and abort() can be a writer making it easy to adapt existing APIs or create specialized implementations without subclassing. There's no complex UnderlyingSink protocol with start(), write(), close(), and abort() callbacks that must coordinate through a controller whose lifecycle and state are independent of the WritableStream it is bound to.
（一）为违法的应用程序提供电子签名、制作、封装、发布或者以测试为名提供下载等服务的；
。关于这个话题，heLLoword翻译官方下载提供了深入分析
self.storages = storages
Филолог заявил о массовой отмене обращения на «вы» с большой буквы09:36