firebase实现问题

import firebase from "firebase/compat/app"
import "firebase/compat/auth"

const app = firebase.initializeApp = ({
apiKey: process.env.REACT_APP_FIREBASE_API_KEY,
authDomain: process.env.REACT_APP_FIREBASE_AUTH_DOMAIN,
projectId: process.env.REACT_APP_FIREBASE_PROJECT_ID,
databaseURL: process.env.REACT_APP_FIREBASE_DATABASE_URL,
storageBucket: process.env.REACT_APP_FIREBASE_STORAGE_BUCKET,
messagingSenderId: process.env.REACT_APP_FIREBASE_MESSAGING_SENDER_ID,
appId: process.env.REACT_APP_FIREBASE_APP_ID
})

export const auth = app.auth()
export default app

问题：TypeError:app.auth不是函数。我希望能够实现firebase身份验证，但我收到了上面的错误。不确定我做错了什么。