public IEnumerator <KeyValuePair <K, T> > GetEnumerator()
        {
            var arrayListEnumerator = KeyValueArray.GetEnumerator();

            while (arrayListEnumerator.MoveNext())
            {
                if (arrayListEnumerator.Current != null)
                {
                    var currentLinkedList    = (LinkedList <KeyValuePair <K, T> >)arrayListEnumerator.Current;
                    var linkedListEnumerator = currentLinkedList.GetEnumerator();
                    while (linkedListEnumerator.MoveNext())
                    {
                        yield return(linkedListEnumerator.Current);
                    }
                }
            }
        }