Django对接cas

# django对接cas
django_cas_ng 版本必须 >= 4.0.1
https://djangocas.dev/docs/4.0/cas-protocol-overview.html

url.py 配置（在project中，而不是app）

```python
from django.contrib import admin
from django.urls import path, include
from django_cas_ng.views import *

login_view = LoginView()
logout_view = LogoutView()
callback_view = CallbackView()
login = login_view.get
logout = login_view.get
callback = callback_view.get

urlpatterns = [
    #--------------------------django_cas login----------------------------#
    path('accounts/login/', login, name='cas_ng_login'),
    path('accounts/logout/', logout, name='cas_ng_logout'),
    path('accounts/callback/', callback, name='cas_ng_callback'),
    #---------------------------------------------------------------------#
    path('admin/', admin.site.urls)
    path('autovm/', include('AutoVM.urls.view_urls', namespace='autovm'))
]
```

settings.py 配置

```python
MIDDLEWARE = [
    '...',
    'django_cas_ng.middleware.CASMiddleware',
]

# Application definition

INSTALLED_APPS = [
    ...
    'django_cas_ng',
]

### CAS Configuration
AUTHENTICATION_BACKENDS = (
  'django.contrib.auth.backends.ModelBackend',
  'django_cas_ng.backends.CASBackend',
)

# CAS 的地址
CAS_SERVER_URL = 'https://cas.sustech.edu.cn/cas/'
# CAS 版本
CAS_VERSION = '3'
# 存入所有 CAS 服务端返回的 User 数据。
CAS_APPLY_ATTRIBUTES_TO_USER = False
# CAS字段转换仅在上一个配置为True时生效,必须启用，其它局点看情况
CAS_RENAME_ATTRIBUTES = {'id' : 'sid', 'ln':'last_name', 'fn':'first_name'}
LOGIN_URL = '/login/'
```