text: #!/usr/bin/env python
  from circuits.web import Controller
  
  from .helpers import urlopen
  
  
  class Root(Controller):
  
      def index(self):
          def response():
              yield "Hello "
              yield "World!"
          return response()
  
  
  def test(webapp):
      f = urlopen(webapp.server.http.base)
      s = f.read()
      assert s == b"Hello World!"
  