How to wait for MPMediaLibrary requestAuthorization response

Im checking the response the user gives when prompted for accessing the media-library. I want to know how can i wait for the response of the user before continuing

static func getAuthrization(completionHandler:@escaping (Bool) -> Void)  {
        var authStatus:Bool=false;
        let status = MPMediaLibrary.authorizationStatus()
        if(status == MPMediaLibraryAuthorizationStatus.authorized){
            authStatus = true
        }else{
            MPMediaLibrary.requestAuthorization() { status in
                if status == .authorized {
                    authStatus = true
                }else{
                    print("Auth not granted")
                    authStatus = false
                }
            }
        }
        completionHandler(authStatus)
    }

This is the function that i use to get user authentication.

func setSongs(){
        print("called from set songs")
        songQuery.getAuthrization { (status) in
            print(status)
        }
    }

And this is the function that i use to call that function

right now the function gets executed and finished before the user response from the system permission prompt. What i want is the for the code to await like in js or dart before executing and then get the response.

Any help is appreciated

Call completionHandler as below,

static func getAuthrization(completionHandler:@escaping (Bool) -> Void)  {
        if MPMediaLibrary.authorizationStatus() == .authorized {
            completionHandler(true)
        } else {
            MPMediaLibrary.requestAuthorization() { completionHandler($0 == .authorized) }
        }
    }