Python练习题4：上周本周下周周一的日期

import datetime import sys def last_monday(date_str): date = datetime.datetime.strptime(datestr,"%Y-%m-%d") date = date + datetime.timedelta(-date.weekday()-7) return date.strftime("%Y-%m-%d") def this_monday(date_str): date = datetime_datetime.strptime(datestr,"%Y-%m-%d") date = date + datetime.timedelta(days = -date.weekday()) return date.strftime("%Y-%m-%d") def next_monday(date_str): date = datetime.datetime.strptime(date_str,"%Y-%m-%d") date = date + datetime.timedelta(-date.weekday()+7) while True: line = sys.stdin.readline() line = line.strip() if line == " ": break print("输入日期："，line) print("上周一："，last_monday(line)) print("本周一：",this_monday(line)) print("下周一："，next_monday(line))