Swift 2 to swift 4 code converting

[MattSaedi]

how can I write this code in swift 4

dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND,0)){ () -> Void in
        
    }

[suyashsrijan]

DispatchQueue.global(qos: .background).async { ... }

[MattSaedi]

thanks