ios – How to add Firebase Messaging to AppDelegate.swift

I have a flutter app where notifications are being sent on android, but not on IOS. I have found the root of the problem to be the lack of FirebaseMessaging being imported into AppDelegate.swift. Firebase’s official documentation is for AppDelegate.swift so I am unsure of how to import it here:

import UIKit
import Flutter
import GoogleMaps

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate {
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
    GMSServices.provideAPIKey("xxxxxxxxxxxxxx")
    GeneratedPluginRegistrant.register(with: self)
    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }
}