firebase.initializeApp(config);
    const db = firebase.firestore();

   const googleSignIn = async () => {
        return await Expo.Google.logInAsync({
            androidClientId,
            iosClientId,
            scopes: ['profile', 'email'],
        });
    };

    const firebaseLogin = async (accessToken) => {
        const cred = firebase.auth.GoogleAuthProvider.credential(null, accessToken);
        await firebase.auth().signInWithCredential(cred).catch(console.error);
        const idToken = await firebase.auth().currentUser.getIdToken(true).catch(console.error);
    };