old_contents: from django.conf.urls import patterns, url
  from django.views.generic.detail import DetailView
  from django.views.generic.list import ListView
  
  from .models import Contribution
  from .views import ContributionCreate, ContributionDelete, ContributionUpdate, ContributionRDF
  
  
  urlpatterns = patterns('',
      url(r'^(all)?/$', ListView.as_view(model=Contribution, queryset=Contribution.published.all()), name='list'),
      # example: /contribution/
      # example: /contribution/all/
      url(r'^add/$', ContributionCreate.as_view(), name='add'),
      # example: /contribution/add/
      url(r'^(?P<pk>\d+)/update/$', ContributionUpdate.as_view(), name='update'),
      # example: /contribution/5/update/
      url(r'^(?P<pk>\d+)/delete/$', ContributionDelete.as_view(), name='delete'),
      # example: /contribution/5/delete/
      url(r'^(?P<pk>\d+)\.xml$', ContributionRDF.as_view(), name='detail_rdf'),
      # example: /contribution/detail_rdf/5/
      url(r'^(?P<pk>\d+)/$', DetailView.as_view(model=Contribution, queryset=Contribution.published.all()), name='detail'),
      # example: /contribution/5/
  )
  
new_contents: from django.conf.urls import patterns, url
  from django.views.generic.detail import DetailView
  from django.views.generic.list import ListView
  
  from .models import Contribution
  from .views import ContributionCreate, ContributionDelete, ContributionUpdate, ContributionRDF
  
  
  urlpatterns = patterns('',
      url(r'^(all/)?$', ListView.as_view(model=Contribution, queryset=Contribution.published.all()), name='list'),
      # example: /contribution/
      # example: /contribution/all/
      url(r'^add/$', ContributionCreate.as_view(), name='add'),
      # example: /contribution/add/
      url(r'^(?P<pk>\d+)/update/$', ContributionUpdate.as_view(), name='update'),
      # example: /contribution/5/update/
      url(r'^(?P<pk>\d+)/delete/$', ContributionDelete.as_view(), name='delete'),
      # example: /contribution/5/delete/
      url(r'^(?P<pk>\d+)\.xml$', ContributionRDF.as_view(), name='detail_rdf'),
      # example: /contribution/detail_rdf/5/
      url(r'^(?P<pk>\d+)/$', DetailView.as_view(model=Contribution, queryset=Contribution.published.all()), name='detail'),
      # example: /contribution/5/
  )
  
subject: Fix the 'contribution/all' or 'contribution/' URL.