new_contents: 
  try:
      from twisted.internet import defer, reactor
  
      def async_sleep(seconds):
          """
          An asynchronous sleep function using twsited.
  
          Source: http://twistedmatrix.com/pipermail/twisted-python/2009-October/020788.html
  
          :type seconds: int
          """
          d = defer.Deferred()
          reactor.callLater(seconds, d.callback, seconds)
          return d
  except ImportError:
      pass
  
subject: add twisted patterns