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<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>ReactJS Training</title>
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css">
    <!--<link rel="stylesheet" href="main.css">-->
    <script src="https://unpkg.com/react@16/umd/react.development.js"></script>
    <script src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"></script>
    <script src="https://unpkg.com/babel-standalone@6.15.0/babel.min.js"></script>
  </head>
  <body>
    <div class="container my-4">
      <div id="container">

      </div>
    </div>
    <script src="app_4.js" type="text/babel"></script>
  </body>
</html>