报错信息:

django.core.exceptions.ImproperlyConfigured: 
Specifying a namespace in include() without providing an app_name is not supported. 
Set the app_name attribute in the included module, 
or pass a 2-tuple containing the list of patterns and app_name instead.

报错中已说明解决办法，设置app_name属性，或者传递一个两个元素的元祖，包含路由匹配列表和app_nameweb

解决办法:

1 在app.urls中声明app_name，与namespace对应

app_name='app'
urlpatterns = [
    url(r'^index/',views.index),
]

2 include方法中传入元祖

urlpatterns = [
    url(r'^app/', include(('app.urls.,'app'), namespace='app')),
]