错误描述：
运行yarn install的时候，出现如下错误：
yarn install v1.21.1
[1/4] 🔍 Resolving packages...
[2/4] 🚚 Fetching packages...
info There appears to be trouble with your network connection. Retrying...
info There appears to be trouble with your network connection. Retrying...
error An unexpected error occurred: "https://registry.npm.taobao.org/@hot-loader/react-dom/download/@hot-loader/react-dom-16.12.0.tgz: unexpected end of file".
info If you think this is a bug, please open a bug report with the information provided in "/Users/zhaowei/Desktop/panamera/jpy-frontend/yarn-error.log".
info Visit https://yarnpkg.com/en/docs/cli/install for documentation about this command.
解决方案：
在运行yarn install文件夹内，新建一个名为.yarnrc的文件，内容如下：
network-timeout 600000
原因：
巨大文件react-dom-16.12.0.tgz下载的时候，超时了，被认为网络链接的问题。因此，我们只要修改网络超时的时间即可。上面文件中的600000是指600000/1000 = 600秒，即5分钟。
