def exportValue(self, vf, value):
        m = StrStrHashMap(value)
        keysAndValues = []
        for i in m.keys():
            keysAndValues.append(i)
            keysAndValues.append(m[i])
def add_item(self, item_value=None, index=None):
    if item_value is None:
      item_value = self._new_item_default_value