pyhton判断闰年

闰年判断：可以被100整除不能被4整除和400整除，闰年2月份是29天，其他的2月是28天

y=int(input("Pls input date: "))
ly=False
if ly<9999:
    if ly%100==0:
        if ly%400==0:
            ly=True
        else:
            ly=False
    elif ly%4==0:
        ly=True
    else:
        ly=False

if ly:
    month_day={1:31,2:29,3:31,4:30,5:31,6:30,7:31,8:31,9:30,10:31,11:30,12:31}
else:
    month_day = {1: 31, 2: 28, 3: 31, 4: 30, 5: 31, 6: 30, 7: 31, 8: 31, 9: 30, 10: 31, 11: 30, 12: 31}

m=int(input('Pls input month: '))
d=int(input('Pls input day: '))
if m not in month_day:
    print('Month value input error')
    exit(1)
if d<1 or d>month_day[m]:
    print("day input error")
    exit(1)

days=0
for i in range(1,m):
    days+=month_day[i]
print('this the the %day'%((days+d)))