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override func viewDidLoad() {
super.viewDidLoad()
let myView = NSHostingView(rootView: MySwiftUIView())
myView.translatesAutoresizingMaskIntoConstraints = false
self.view.addSubview(myView)
myView.centerYAnchor.constraint(equalTo: self.view.centerYAnchor).isActive = true
myView.centerXAnchor.constraint(equalTo: self.view.centerXAnchor).isActive = true
}