def exportValue(self, vf, value):
        m = StrStrHashMap(value)
        keysAndValues = []
        for i in m.keys():
            keysAndValues.append(i)
            keysAndValues.append(m[i])
def _get(delta, start):
            p = start
            while delta:
                p = p.next
                delta -= 1
            return p.val