I want to add Label , where should i write the code to add label? : I want to add Label , where should i write the code to add label ?**strong text**

import UIKit

class ViewController: UIViewController {
    
    override func viewDidLoad() {
        super.viewDidLoad()
      
        // Do any additional setup after loading the view, typically from a nib.
        
        
        
        var x = 20.0
        var y = 100.0
        let width = 100.0
        
        let offsetX = 80.0
        let offsetY = 80.0
        
        for i in 1 ... 9 {
            
            let button = UIButton(frame: CGRect(x: x, y: y, width: width, height: width))
            button.tag = i
            button.setTitle("\(i)", for: UIControlState.normal)
            button.setTitleColor(UIColor.green, for: UIControlState.normal)
            button.addTarget(self, action: #selector(self.buttonPressed(button:)), for: UIControlEvents.touchUpInside)
            self.view.addSubview(button)
            
            x = x + offsetX
            
            if i%3 == 0 {
                
                y = y + offsetY
                x = 20.0
                
            }
            
        }
        
    }
    
    
    @objc func buttonPressed (button:UIButton) {
        
        print("Button Pressed: \(button.tag)")
        
    }
    
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
}
}

I want to add Label , where should i write the code to add label ?