在python中输入年月日确定星期几？

import calendar
from calendar import *
import datetime
y = input('请输入年份')
m = input('请输入月份')
d = input('请输入日')
lis = ['星期一','星期二','星期三','星期四','星期五','星期六','星期日',]
dic = dict(enumerate(lis))
if y.isdigit() and m.isdigit() and d.isdigit() and 1<=int(m)<=12 and 1<=int(d)<=31 :
    w = weekday(int(y),int(m),int(d))       
    print(dic[w])