     optional func tasksDuringTransition(operation: UINavigationControllerOperation) -> [Task]
 }
 
+// Protocol Animation
+
 @objc
 protocol Animation {
     var valueAfterAnimation: AnyObject { get }

}

class Animator {
    var duration: NSTimeInterval {

        var duration = 0.0


        present.tasks = tasks
    }
}

extension Manager: UIViewControllerAnimatedTransitioning {

    func animateTransition(context: UIViewControllerContextTransitioning) {
        start(context)
    }
