old_contents: import React from 'react';
  import { Route, Routes } from 'react-router-dom';
  import Home from './Home';
  import './App.css';
  
  const App = () => (
    <Routes>
      <Route path="/" element={<Home/>} />
    </Routes>
  );
  
  export default App;
  
new_contents: import React from 'react';
  import { Route, Switch } from 'react-router-dom';
  import Home from './Home';
  import './App.css';
  
  const App = () => (
    <Switch>
      <Route path="/" element={<Home/>} />
    </Switch>
  );
  
  export default App;
  
subject: use switch not routes