def test_iterableAfterRead(self):
        """
        Iterating over L{_InputStream} after calling L{_InputStream.read}
        produces lines from the input stream starting from the first byte after
        the last byte returned by the C{read} call.
        """
        bytes = b"green eggs\nand ham\n"
        def iterate(input):
            input.read(3)
            return list(input)
        d = self._renderAndReturnReaderResult(iterate, bytes)
        d.addCallback(self.assertEqual, [b"en eggs\n", b"and ham\n"])
        return d

        Iterating over L{_InputStream} after calling L{_InputStream.read}
        produces lines from the input stream starting from the first byte after
        the last byte returned by the C{read} call.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/test/test_wsgi.py