定义django admin的站点头，标题等

admin.py

from django.contrib import admin
from app.models import Product
# Register your models here.

class MyAdminSite(admin.AdminSite):
    site_header = '我的管理网站'

admin_site = MyAdminSite()

#使用admin_site实例注册需要管理的模型类
admin_site.register(Product)

修改urls.py

from django.conf.urls import url, include
from django.contrib import admin
from app.admin import admin_site

urlpatterns = [
    url(r'^admin/', admin_site.urls),    #修改这一行
    url(r'^app/', include('app.urls')),
]

AdminSite中常用的定制属性：

site_header: 每个管理网页的页头都会出现的标题

site_title:   页面标题，<title></title>中的内容

site_url:    管理站点中View site的目标地址

login_form:  登录页面使用的AuthenticationForm子类名