import datetime


def last_first_date_and_last_date(n):
    """
    獲取前n周開始時間和結束時間，引數n：代表前n周
    :param n: int型別 數字：1，2，3，4，5
    :return: 返回前n周的週一0點時間  和 週日23點59分59秒
    """
    now = datetime.datetime.now()
    before_n_week_start = now - datetime.timedelta(days=now.weekday() + 7 * n, hours=now.hour, minutes=now.minute,
                                                   seconds
 
=now.second, microseconds=now.microsecond)
    before_n_week_end = before_n_week_start + datetime.timedelta(days=6, hours=23, minutes=59, seconds=59)
    return before_n_week_start, before_n_week_end


def get_week_monday_and_sunday_by_date(date_str):
    """
    給定一個日期-返回日期所在周的週一0點時間 和 週日23點59分59秒
    :param date_str: 如："2020-05-01"
    :return: 給定一個日期-返回日期所在周的週一0點時間 和 週日23點59分59秒
    
 
"""
    now_time = datetime.datetime.strptime(date_str + " 00:00:00", "%Y-%m-%d %H:%M:%S")
    week_start_time = now_time - datetime.timedelta(days=now_time.weekday(), hours=now_time.hour,
                                                    minutes=now_time.minute, seconds=now_time.second,
                                                    microseconds
 
=now_time.microsecond)
    week_end_time = week_start_time + datetime.timedelta(days=6, hours=23, minutes=59, seconds=59)
    return week_start_time, week_end_time


def get_all_monday_and_sunday_by_date_interval(start_date_str, end_date_str):
    """
    給定時間（日期）區間，返回區間中所有的周起止時間列表（不含本週）
    :param start_date_str: "2020-01-31"
    :param end_date_str: "2020-05-08"
    :return:
    """
    date_list = list()

    # 本週一開始時間
    now = datetime.datetime.now()
    now_week_monday = now - datetime.timedelta(days=now.weekday(), hours=now.hour, minutes=now.minute,
                                               seconds=now.second, microseconds=now.microsecond)
    print('now_week_monday = {}'.format(now_week_monday))

    # 起始時間所在周 - 週一和週日
    start_week_monday, start_week_sunday = get_week_monday_and_sunday_by_date(start_date_str)
    print('start_week = {} -> {}'.format(start_week_monday, start_week_sunday))

    # 截止時間所在周 - 週一和週日
    end_week_monday, end_week_sunday = get_week_monday_and_sunday_by_date(end_date_str)
    print('end_week = {} -> {}'.format(end_week_monday, end_week_sunday))
    if end_week_monday < now_week_monday:
        date_list.append({"start_time": end_week_monday, "end_time": end_week_sunday})

    count = 1
    while True:
        week_start_time = end_week_monday - datetime.timedelta(days=7 * count)
        week_end_time = week_start_time + datetime.timedelta(days=6, hours=23, minutes=59, seconds=59)
        print('middle_week = {} -> {}'.format(week_start_time, week_end_time))

        count += 1
        if week_start_time >= now_week_monday:
            continue
        if week_start_time < start_week_monday:
            break
        print('append middle_week = {} -> {}'.format(week_start_time, week_end_time))
        date_list.append({"start_time": week_start_time, "end_time": week_end_time})
    return date_list

摘自別人，只做備忘