def test_produce_one_keyword(self): 

       l = []

       py.log.setconsumer('s1', l.append) 

->     py.log.Producer('s1')("hello world") 

       assert len(l) == 1

       msg = l[0]

       assert msg.content().startswith('hello world') 

       assert msg.prefix() == '[s1] ' 

       assert str(msg) == "[s1] hello world"