GAE的页面定向问题，求高手帮忙看一下

from google.appengine.api import memcache
from google.appengine.ext import webapp
from google.appengine.ext.webapp.util import run_wsgi_app
import os

class usertest(webapp.RequestHandler):
def get(self):
user = memcache.get('user')
if user == None:
self.redirect('/login', '/')
else:
self.response.out.write("欢迎回来"+user.uname)


class login(webapp.RequestHandler):
def get(self):
self.response.headers['Content-Type'] = 'text/html'
self.response.out.write("login")


class auth(webapp.RequestHandler):
def get(self):
if True:
self.redirect(self.request.get('redirect'))


application = webapp.WSGIApplication([('/', usertest),('/login',login),('/auth',auth),],
debug=True)


def main():
run_wsgi_app(application)


if __name__ == '__main__':
main()

这段代码中本地运行以后，输入localhost:8080/login以后总是返回404错误，直接输入localhost:8080就可以随意定向到哪个页面。
配置文件app.yaml如下
application: usertest
version: 1
runtime: python
api_version: 1

handlers:
- url: /*
script: usertest.py
求高手帮忙看一下是为什么