iOS Swift. How to hide back Button Text in UINavigationBar

By default in Navigation Controller the title of back button of current view controller is the title of previous view controller. But what if we want not show any text for back button and show only symbol "<". For that purpose we have to replace in first view controller back button for navigation item.

import UIKit

class ParentViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Remove title from back button. Now only "<" symbol will be show as back button.
        let backButton = UIBarButtonItem(title: "", style: .plain, target: nil, action: nil)
        self.navigationItem.backBarButtonItem = backButton
    }

}

Standard "back button"

No text Back Button