def test_unsupportedCompression(self):
        """
        A zipfile which describes an unsupported compression mechanism should
        raise BadZipfile.
        """
        fn = self.mktemp()
        with zipfile.ZipFile(fn, "w") as zf:
            zi = zipfile.ZipInfo("0")
            zf.writestr(zi, "some data")
            # Mangle its compression type in the central directory; can't do
            # this before the writestr call or zipfile will (correctly) tell us
            # not to pass bad compression types :)
            zi.compress_type = 1234

        with zipstream.ChunkingZipFile(fn) as czf:
            self.assertRaises(zipfile.BadZipfile, czf.readfile, "0")

        A zipfile which describes an unsupported compression mechanism should
        raise BadZipfile.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/test/test_zipstream.py