计算每天，每周，每月的时间范围

Question

给出一个时间戳，我想计算它周围的时间窗口。例如，如果时间是5月3日，我应该获得5月1日至5月31日的每月窗口。每天或每周都一样。

以下代码适用于每日和每月，如何编写每周窗口？

import datetime

# given a time, get the 1st and last times of its window
def get_timeslot(window,t):
    if(window==1): # monthly window
        t2 = t.replace(day=1, hour=0, minute=0, second=0, microsecond=0)
        if(t2.month==12):
            m = 1
            y = t2.year+1
        else:
            m = t2.month+1
            y = t2.year
        t3 = t2.replace(year=y,month=m) - datetime.timedelta(microseconds=1)
    elif(window==2): # weekly window
        pass
    elif(window==3): # daily window
        t2 = t.replace(hour=0, minute=0, second=0, microsecond=0)
        t3 = t.replace(hour=23, minute=59, second=59, microsecond=999999)
    else:
        t2 = None
        t3 = None
    return t2,t3

t1 = datetime.datetime.utcnow()
print(t1, t1.year, t1.month, t1.day, t1.hour, t1.minute, t1.second, t1.microsecond, t1.tzinfo)
for i in range(14):
    t2,t3 = get_timeslot(3, t1)
    print(t2, '----',t3)
    t1 = t3 + datetime.timedelta(microseconds=1)