老师好,6-2章节登录后提示报错如下,检查了一遍没找到什么问题:

from users.views import login
urlpatterns = [
url(r'^xadmin/', xadmin.site.urls),
url('^$',TemplateView.as_view(template_name="index.html"),name="index"),
url('^login/$',login,name="login")
]from django.shortcuts import render
from django.contrib.auth import authenticate
# Create your views here.
def login(request):
if request.method == "POST":
user_name = request.POST.get("username","")
pass_word = request.POST.get("password","")
user = authenticate(user_name,pass_word)
if user is not None:
login(request,user)
return render(request,"index.html")
else:
return render(request, "login.html", {})
elif request.method == "GET":
return render(request,"login.html",{})