我正在Swift3中开发应用程序，但遇到字母问题，我找不到答案。

我怎么知道基于纬度和经度的城市名称和国家简称？

import UIKit
import CoreLocation

class ViewController: UIViewController, CLLocationManagerDelegate{
    let locationManager = CLLocationManager()
    var latitude: Double = 0
    var longitude: Double = 0
    override func viewDidLoad() {
        super.viewDidLoad()
        // For use when the app is open & in the background
        locationManager.requestAlwaysAuthorization()
        // For use when the app is open
        //locationManager.requestWhenInUseAuthorization()
        locationManager.delegate = self
        locationManager.startUpdatingLocation()
        if CLLocationManager.locationServicesEnabled() {
            locationManager.delegate = self
            locationManager.desiredAccuracy = kCLLocationAccuracyBest
            locationManager.startUpdatingLocation()
        }
    }
    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        if let location = locations.first {
            print(location.coordinate)
            latitude = location.coordinate.latitude
            longitude = location.coordinate.longitude
        }
    }
    func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
        if (status == CLAuthorizationStatus.denied){
            showLocationDisabledpopUp()
        }
    }
    func showLocationDisabledpopUp() {
        let alertController = UIAlertController(title: "Background Location Access  Disabled", message: "We need your location", preferredStyle: .alert)
        let cancelAction = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)
        alertController.addAction(cancelAction)
        let openAction = UIAlertAction(title: "Open Setting", style: .default) { (action) in
            if let url = URL(string: UIApplicationOpenSettingsURLString){
                UIApplication.shared.open(url, options: [:], completionHandler: nil)
            }
        }
        alertController.addAction(openAction)
        self.present(alertController, animated: true, completion: nil)
    }
}