     public required init(objects: UnsafePointer<AnyObject>!, forKeys keys: UnsafePointer<NSObject>!, count cnt: Int) {
         super.init(objects: objects, forKeys: keys, count: cnt)
     }
-    
-}
-
-extension NSMutableDictionary {
-    
+
     open func addEntries(from otherDictionary: [AnyHashable : Any]) {
         for (key, obj) in otherDictionary {
             setObject(obj, forKey: key)

            _storage[key as! NSObject] = value
        }
    }
    
    public required convenience init?(coder aDecoder: NSCoder) {
        guard aDecoder.allowsKeyedCoding else {
            preconditionFailure("Unkeyed coding is unsupported.")

        } else {
            return object(forKey: key)
        }
    }
    
    open func keyEnumerator() -> NSEnumerator {
