gistfile1.txt

import { createStore } from "redux";
import { Provider } from "react-redux";
import Header from "./Header";

const initialState = { username: "Farshid" };
const returnStateReducer = (state = initialState, action) => {
 if (action.type === "updateUser") {
  return { ...state, username: "Farhad" };
 } else {
  return state;
 }
};
const store = createStore(returnStateReducer);
const App = () => {
 return (
  <Provider store={store}>
   <div>
    <Header />
    <h1>Hello World</h1>
   </div>
  </Provider>
 );
};
export default App;