If I create URL

```
urlpatterns = patterns('',     
     url(r'^admin/', include(admin.site.urls)),
     url(r'^about/',views.about , name = 'about'),
     url(r'^rango/',views.index, name = 'index'),
)

```

the link `127.0.0.1:8000/about` and `127.0.0.1:8000/about/about/` will direct you to same page isn't it? How do I stop that ? I only want 

```
domain-name/about/  

```

to be valid and anything (`/about/about/about/...`) should be invalid page.