python使用openpyxl读取日期并修改excel

import datetime
import openpyxl
from openpyxl.worksheet.worksheet import Worksheet


# 读取excel表格中的日期
def xldate_as_datetime(xldate, datemode=0):
    if datemode not in (0, 1):
        raise Exception(datemode)
    if xldate == 0.00:
        return datetime.time(0, 0, 0)
    if xldate < 0.00:
        raise Exception(xldate)
    xldays = int(xldate)
    frac = xldate - xldays
    seconds = int(round(frac * 86400.0))
    assert 0 <= seconds <= 86400
    if seconds == 86400:
        seconds = 0
        xldays += 1
    # if xldays >= _XLDAYS_TOO_LARGE[datemode]:
    #    raise XLDateTooLarge(xldate)
    if xldays == 0:
        # second = seconds % 60; minutes = seconds // 60
        minutes, second = divmod(seconds, 60)
        # minute = minutes % 60; hour    = minutes // 60
        hour, minute = divmod(minutes, 60)
        return datetime.time(hour, minute, second)
    if xldays < 61 and datemode == 0:
        raise Exception(xldate)
    return (
            datetime.datetime.fromordinal(xldays + 693594 + 1462 * datemode)
            + datetime.timedelta(seconds=seconds)
    )


if __name__ == '__main__':
    # 读取excel
    workbook = openpyxl.load_workbook("D:\pythonwork\mindscrapy\朱志文.xlsx")
    # 获取工作簿
    sheet: Worksheet = workbook['Sheet1']
    # 获取S列
    sl = sheet['S']
    temp = None
    for s in sl:
        value = s.value
        if value is not None:
            # 私有方法-数字转成日期
            t = xldate_as_datetime(value)
            # 去掉时间，保留日期
            as_datetime = str(t)[0:10]
            # 重新赋值
            s.value = as_datetime
            # 修改临时值
            temp = as_datetime
        else:
            # 如果是空的，采用上一个值
            s.value = temp
    # 保存为新的excel
    workbook.save('D:\pythonwork\mindscrapy\朱志文00.xlsx')