def importHelper(self, struct):
        m = StrStrHashMap()
        keysAndValues = struct.get(self.__field)
        for i in range(0, len(keysAndValues), 2):
            m[keysAndValues[i]] = keysAndValues[i+1]
        return m
def _load_from_file(self, fn):
        self._filename = fn
        with open(fn, "r") as f:
            try:
                replay_data = json.load(f)
            except json.decoder.JSONDecodeError as e:
                raise TransactionReplayError(fn, str(e) + ".")

        try:
            self._load_from_data(replay_data)
        except TransactionError as e:
            raise TransactionReplayError(fn, e)