Django前台应用无法加载React组件。

Question

我以下 Tranversy Media Django-React教程。. 服务器运行OK后，但我的App.js文件中的组件不显示在index.html中。请大家帮助一下，可能是什么问题。

这是我的项目树。见图

然后是我的app.js

import React, {Component} from 'react';
import ReactDOM from 'react-dom';

class App extends Component {
    render() {
        return <h1>React App</h1>
    }
}
ReactDOM.render(<App />, document.getElementById("app"));

我的index.html

<meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link rel="stylesheet" href="https://bootswatch.com/4/cosmo/bootstrap.min.css">  

    <title>Lead Manager</title>

    {%load static%}

</head>

<body>
    <h1></h1>
    <div id="app"></div>

    <script>src="{%static "frontend/main.js"%}"</script>
    <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js" integrity="sha384-UO2eT0CpHqdSJQ6hJty5KVphtPhzWj9WO1clHTMGa3JDZwrnQq4sF86dIHNDz0W1" crossorigin="anonymous"></script>
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous"></script>
</body>

webpack.index.js

import App from './components/App';

webpack.config.js

module.exports = {
    module: {
        rules: [{
            test: /.js$/,
            exclude: /node_modules/,
            use: {
                loader:"babel-loader"
            }
        }]
    }
}

后台使用api工作正常。