用django自带的用户登录怎么实现

url.py

urlpatterns = patterns('',
  (r'^accounts/login/$','django.contrib.auth.views.login'),
  )


然后模板里有templates/registration/login.html

访问http://127.0.0.1:8000/accounts/login/
怎么刷不出登录页面，
  报错
  raise TemplateDoesNotExist(name)
  TemplateDoesNotExist: 500.html
views.py里需不需要写login函数，但是我用自带的啊
求教。


TEMPLATE_LOADERS = (
  'django.template.loaders.filesystem.Loader',
  'django.template.loaders.app_directories.Loader',
# 'django.template.loaders.eggs.Loader',
)

MIDDLEWARE_CLASSES = (
  'django.middleware.common.CommonMiddleware',
  'django.contrib.sessions.middleware.SessionMiddleware',
  'django.middleware.csrf.CsrfViewMiddleware',
  'django.contrib.auth.middleware.AuthenticationMiddleware',
  'django.contrib.messages.middleware.MessageMiddleware',
  'django.middleware.csrf.CsrfResponseMiddleware',
)

ROOT_URLCONF = 'mysite.urls'

TEMPLATE_DIRS = (
  # Put strings here, like "/home/html/django_templates" or "C:/www/django/templates".
  # Always use forward slashes, even on Windows.
  # Don't forget to use absolute paths, not relative paths.
  "/home/mark/djangocode/mysite/templates",
)

INSTALLED_APPS = (
  'mysite.books',
  'mysite.messageboard',
  'django.contrib.auth',
  'django.contrib.contenttypes',
  'django.contrib.sessions',
  'django.contrib.sites',
  'django.contrib.comments',
  'django.contrib.messages',
  'django.contrib.staticfiles',
  # Uncomment the next line to enable the admin:
  'django.contrib.admin',
  # Uncomment the next line to enable admin documentation:
  'django.contrib.admindocs',
)



还需要什么配置？

求大仙帮忙