正则错误

[epirus]

import re
TIMEZONE_PATTERN = re.compile(re.compile(r"([+\-])([0-9])?([0-9])?([0-9])?([0-9])?"))

TIMEZONE_PATTERN.match('2021-09-18 13:21:44').groups()

Traceback (most recent call last): File "", line 4, in AttributeError: 'NoneType' object has no attribute 'groups'

这个为什么会报错