IOS 10 Swift Playground : NASA APOD

/**
 Compatible with the iOS 10 Beta 1 Swift Playgrounds app
 
 The code below talks to NASA's "Astronomy Picture of the Day" API endpoint to download the latest picture.  After running the code, the picture is viewable by tapping the image literal that appears in the right-hand margin as indicated by a comment.
 
 note:  Must replace "YOUR API KEY" on the first line of code, with a your personally-generated NASA api key. See the following link to get your API key:  https://api.nasa.gov/index.html#apply-for-an-api-key
 */
import Foundation
import UIKit

let apikey = "YOUR API KEY"
let url = URL(string: "https://api.nasa.gov/planetary/apod?api_key=\(apikey)")!
let apodJSONData = try Data(contentsOf: url)
do {
    guard let apodJSON = try JSONSerialization.jsonObject(with: apodJSONData, options: JSONSerialization.ReadingOptions.allowFragments) as? [String:AnyObject] 
        else {
            throw NSError(domain: "no json", code: 0, userInfo: nil)
    }
    
    print(apodJSON)
    
    guard let imageURLString = apodJSON["url"] as? String 
        else {
            throw NSError(domain: "no url in json", code: 0, userInfo: nil)
    }
    guard let imageURL = URL(string: imageURLString) 
        else {
            throw NSError(domain: "json url is not a url", code: 0, userInfo: nil)
    }
    
    let imageData = try Data(contentsOf: imageURL)
    
    let image = UIImage(data: imageData, scale: 1)  //Final downloaded image --->
    
}
catch {
    print(error)
}