python 判断平年还是闰年

while 1:
   s = input('请填入一个年份：')
   s = int(s)

   year = False

   if s % 100 == 0 and s % 400 == 0:
      year = True   

   elif s % 100 != 0 and s % 4 == 0:   

      year = True

   if year:
      print('闰年')
   else:
      print('平年')