     }
 
     /// SwifterSwift: Anchor center X and Y into current view's superview
-    @available(iOS 9, *)
     func anchorCenterSuperview() {
         // https://videos.letsbuildthatapp.com/
         anchorCenterXToSuperview()

    /// - Parameters:
    ///   - withFormat: visual Format language
    ///   - views: array of views which will be accessed starting with index 0 (example: [v0], [v1], [v2]..)
    @available(iOS 9, *) func addConstraints(withFormat: String, views: UIView...) {
        // https://videos.letsbuildthatapp.com/
        var viewsDictionary: [String: UIView] = [:]
        for (index, view) in views.enumerated() {

    ///   - widthConstant: current view's width
    ///   - heightConstant: current view's height
    /// - Returns: array of newly added constraints (if applicable).
    @discardableResult
    func anchor(
        top: NSLayoutYAxisAnchor? = nil,
