I am trying to translate the following from Objective-C to Swift, but I'm stuck!
See https://developer.apple.com/documentation/appkit/nsapplicationlaunchusernotificationkey
NSUserNotification *userNotification = [[myNotification userInfo]
objectForKey:NSApplicationLaunchUserNotificationKey];
if (userNotification) {
// The app was launched by a user selection from Notification Center.
}