System.Collections.Generic.Dictionary<string, int> dic = new System.Collections.Generic.Dictionary<string, int>();
        System.Collections.ObjectModel.ReadOnlyDictionary<string, int> o = new System.Collections.ObjectModel.ReadOnlyDictionary<string, int>(dic);
        Dictionary<string, int> l1 = o.ToDictionary<string, int>(S => dic[S.Key]);