python - 如何使用基于星期几的日期时间创建日期？

Question

我想使用 datetime 编写一段代码，这样如果 datetime.now() 是星期六或星期五下午 4 点之后，就在星期五过去了。

我已完成以下内容:

from datetime import datetime

datenow = datetime.now()
if datenow.isoweekday() == 6 or (datenow.isoweekday() in [5] and datenow.hour >=16): 
           ## change datenow to the passing friday at 4pm.

有人可以帮帮我吗？

Answer 1

完整解决方案:

def set_prev_iso_week_day(val, iso_week_day):
    """
    Set ISO week day.
    New date will be less or equal than input date.
    :param val: datetime or date
    :type val: datetime.datetime | datetime.date
    :param iso_week_day: ISO week day to set
    :type iso_week_day: int
    :return: datetime.datetime | datetime.date
    """
    if val.isoweekday() == iso_week_day:
        return val
    diff = iso_week_day - val.isoweekday()
    diff = -diff if diff < 0 else 7 - diff
    val -= timedelta(days=diff)
    return val

datenow = set_prev_iso_week_day(datenow, 5).replace(hour=16,minute=0,second=0,microsecond=0)

或者使用我的库 t77_date并使用:

from t77_date.constants import ISO_FRIDAY
from t77_date.datetime import set_prev_iso_week_day


datenow = set_prev_iso_week_day(datenow, ISO_FRIDAY).replace(hour=16,minute=0,second=0,microsecond=0)