def test_resumeProducingProducesContent(self):
        """
        L{MultipleRangeStaticProducer.resumeProducing} writes the requested
        chunks of content from the resource to the request, with the supplied
        boundaries in between each chunk.
        """
        request = DummyRequest([])
        content = b'abcdef'
        producer = static.MultipleRangeStaticProducer(
            request, StringIO(content), [(b'1', 1, 3), (b'2', 5, 1)])
        # DummyRequest.registerProducer pulls all output from the producer, so
        # we just need to call start.
        producer.start()
        self.assertEqual(b'1bcd2f', b''.join(request.written))

        L{MultipleRangeStaticProducer.resumeProducing} writes the requested
        chunks of content from the resource to the request, with the supplied
        boundaries in between each chunk.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/test/test_static.py