npm start

Galera beleza, então meu código está igual o do professor, mas quando eu tento executar no terminal o npm start, não da erro no terminal mas na página do app da esse erro, quem puder ajudar desde ja agradeço

TypeError: Cannot set property 'props' of undefined
Component
C:/Users/renan/Documents/alura_cursos/react/ceep/node_modules/react/cjs/react.development.js:322
  319 | 
  320 | 
  321 | function Component(props, context, updater) {
> 322 |   this.props = props;
  323 |   this.context = context; // If a component has string refs, we will assign a different object later.
  324 | 
  325 |   this.refs = emptyObject; // We initialize the default updater but the real one gets injected by the
View compiled
Module.<anonymous>
C:/Users/renan/Documents/alura_cursos/react/ceep/src/App.js:5
  2 | import ListaDeNotas from './components/ListaDeNotas';
  3 | import FormularioCadastro from './components/FormularioCadastro';
  4 | 
> 5 | class App extends Component() {
  6 | 
  7 |   render() {
  8 |     return (
View compiled
Module../src/App.js
http://localhost:3000/static/js/main.chunk.js:145:30
__webpack_require__
C:/Users/renan/Documents/alura_cursos/react/ceep/webpack/bootstrap:851
  848 | 
  849 | __webpack_require__.$Refresh$.init();
  850 | try {
> 851 |     modules[moduleId].call(module.exports, module, module.exports, hotCreateRequire(moduleId));
      | ^  852 | } finally {
  853 |     __webpack_require__.$Refresh$.cleanup(moduleId);
  854 | }
View compiled
fn
C:/Users/renan/Documents/alura_cursos/react/ceep/webpack/bootstrap:150
  147 |         );
  148 |         hotCurrentParents = [];
  149 |     }
> 150 |     return __webpack_require__(request);
      | ^  151 | };
  152 | var ObjectFactory = function ObjectFactory(name) {
  153 |     return {
View compiled
▶ 2 stack frames were collapsed.
__webpack_require__
C:/Users/renan/Documents/alura_cursos/react/ceep/webpack/bootstrap:851
  848 | 
  849 | __webpack_require__.$Refresh$.init();
  850 | try {
> 851 |     modules[moduleId].call(module.exports, module, module.exports, hotCreateRequire(moduleId));
      | ^  852 | } finally {
  853 |     __webpack_require__.$Refresh$.cleanup(moduleId);
  854 | }
View compiled
fn
C:/Users/renan/Documents/alura_cursos/react/ceep/webpack/bootstrap:150
  147 |         );
  148 |         hotCurrentParents = [];
  149 |     }
> 150 |     return __webpack_require__(request);
      | ^  151 | };
  152 | var ObjectFactory = function ObjectFactory(name) {
  153 |     return {
View compiled
1
http://localhost:3000/static/js/main.chunk.js:760:18
__webpack_require__
C:/Users/renan/Documents/alura_cursos/react/ceep/webpack/bootstrap:851
  848 | 
  849 | __webpack_require__.$Refresh$.init();
  850 | try {
> 851 |     modules[moduleId].call(module.exports, module, module.exports, hotCreateRequire(moduleId));
      | ^  852 | } finally {
  853 |     __webpack_require__.$Refresh$.cleanup(moduleId);
  854 | }
View compiled
checkDeferredModules
C:/Users/renan/Documents/alura_cursos/react/ceep/webpack/bootstrap:45
  42 |     }
  43 |     if(fulfilled) {
  44 |         deferredModules.splice(i--, 1);
> 45 |         result = __webpack_require__(__webpack_require__.s = deferredModule[0]);
     | ^  46 |     }
  47 | }
  48 | 
View compiled
Array.webpackJsonpCallback [as push]
C:/Users/renan/Documents/alura_cursos/react/ceep/webpack/bootstrap:32
  29 |     deferredModules.push.apply(deferredModules, executeModules || []);
  30 | 
  31 |     // run deferred modules when all chunks ready
> 32 |     return checkDeferredModules();
     | ^  33 | };
  34 | function checkDeferredModules() {
  35 |     var result;
View compiled
(anonymous function)
http://localhost:3000/static/js/main.chunk.js:1:61
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