def get_id(self, version: int) -> str:
    assert (version >= 2)
    res = []
    for i in range(len(self.ops)):
        res.append(_id_operator_v2[self.ops[i]])
        res.append(self.exprs[i].get_id(version))
    res.append(self.exprs[(- 1)].get_id(version))
    return ''.join(res)
def get_id(self, version: int) -> str:
    assert (version >= 2)
    res = []
    for i in range(len(self.ops)):
        res.append(_id_operator_v2[self.ops[i]])
        res.append(self.exprs[i].get_id(version))
    res.append(self.exprs[(- 1)].get_id(version))
    return .join(res)