Aprove answer
public lazy var managedObjectModel: NSManagedObjectModel = {
        // The managed object model for the application. This property is not optional. It is a fatal error for the application not to be able to find and load its model.
        let modelURL = NSBundle.mainBundle().URLForResource("CoreDataWatch", withExtension: "momd")!
        return NSManagedObjectModel(contentsOfURL: modelURL)!

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