1990年1月1号是星期一，输入年月日转为星期几

def date_to_week(year,month,day):
    runnian_days = [31,29,31,30,31,30,31,31,30,31,30,31]
    pingnian_days = [31,28,31,30,31,30,31,31,30,31,30,31]
    if year>=1990:
        year_days = 0
        for y in range(1990,year):
            if y%400==0 or (y%4==0 and y%100!=0):
                year_days = year_days+366
            else:
                year_days = year_days+365
        print(year_days)
        if year % 400 == 0 or (year % 4 == 0 and year % 100 != 0):
            month_days = sum(runnian_days[0:month-1])
        else:
            month_days = sum(pingnian_days[0:month - 1])
        print(month_days)
        all_days= year_days+month_days+day
        print(all_days)
        dict_week ={0:"星期天",1:"星期一",2:"星期二",3:"星期三",4:"星期四",5:"星期五",6:"星期六"}
        return dict_week[all_days%7]
    else:
        year_days = 0
        for y in range(year,1990):
            if y%400==0 or (y%4==0 and y%100!=0):
                year_days = year_days+366
            else:
                year_days = year_days+365
        print(year_days)
        if year % 400 == 0 or (year % 4 == 0 and year % 100 != 0):
            month_days = sum(runnian_days[0:month-1])
        else:
            month_days = sum(pingnian_days[0:month - 1])
        print(month_days)
        all_days= year_days-month_days-day
        print(all_days)
        dict_week ={0:"星期天",1:"星期六",2:"星期五",3:"星期四",4:"星期三",5:"星期二",6:"星期一"}
        return dict_week[all_days%7]

r = date_to_week(1989,6,16)
print(r)