old_contents: '''
  Django-style URL dispatcher view.
  
      App(root_url=url_dispatcher([
          (r'^/$', views.index),
          (re.compile(r'^/(?P<foo>\d+)/'), views.detail, {'bar': True}),
      ])
  
  The view will be called with the request, and any matched _named_ groups.
  Extra kwargs can be passed as a 3rd positional argument.
  
  There is a namedtuple class defined called URL provided.  All patterns will be
  assembled as a URL instance, and their regex compiled.  If kwargs are not
  specified, they will default to {}.
  '''
  
  from collections import namedtuple
  
  import re
  from . import response
  
  class KeepLooking(Exception):
      '''Used to tell a url_dispatcher to skip this pattern and keep looking.'''
      pass
  
  URL = namedtuple('url', ('regex', 'view'))
  
  class url_dispatcher(object):
      def __init__(self, patterns):
          self.patterns = map(self._make_url, patterns)
  
      def _make_url(self, pattern):
          '''Helper to ensure all patterns are url instances.'''
          if not isinstance(pattern, URL):
              # Ensure the regex is compiled
              pattern = URL(re.compile(pattern[0]), pattern[1])
          return pattern
  
      def __call__(self, request, *args, **kwargs):
          path = getattr(request, 'remaining_path', request.path)
          for pattern in self.patterns:
              m = pattern.regex.match(path)
              if m:
                  path.remaining_path = path[:m.end()]
                  try:
                      return pattern.view(request, *args, **kwargs)
                  except KeepLooking:
                      pass
  
          return self.handle_not_found(request)
  
      def handle_not_found(self, request):
          return response.NotFound()
  
new_contents: '''
  Django-style URL dispatcher view.
  
      App(root_url=url_dispatcher([
          (r'^/$', views.index),
          (re.compile(r'^/(?P<foo>\d+)/'), views.detail, {'bar': True}),
      ])
  
  The view will be called with the request, and any matched _named_ groups.
  Extra kwargs can be passed as a 3rd positional argument.
  
  There is a namedtuple class defined called URL provided.  All patterns will be
  assembled as a URL instance, and their regex compiled.  If kwargs are not
  specified, they will default to {}.
  '''
  
  from collections import namedtuple
  
  import re
  from . import response
  
  class KeepLooking(Exception):
      '''Used to tell a url_dispatcher to skip this pattern and keep looking.'''
      pass
  
  URL = namedtuple('url', ('regex', 'view'))
  
  class url_dispatcher(object):
      def __init__(self, patterns):
          self.patterns = map(self._make_url, patterns)
  
      def _make_url(self, pattern):
          '''Helper to ensure all patterns are url instances.'''
          if not isinstance(pattern, URL):
              # Ensure the regex is compiled
              pattern = URL(re.compile(pattern[0]), pattern[1])
          return pattern
  
      def __call__(self, request, *args, **kwargs):
          path = getattr(request, 'remaining_path', request.path)
          for pattern in self.patterns:
              m = pattern.regex.match(path)
              if m:
                  request.remaining_path = path[:m.end()]
                  try:
                      return pattern.view(request, *args, **kwargs)
                  except KeepLooking:
                      pass
  
          return self.handle_not_found(request)
  
      def handle_not_found(self, request):
          return response.NotFound()
  
subject: Update urls.py