def test_file(self):
        """
        An L{XMLFile} with a file object returns a useful repr().
        """
        fobj = StringIO("not xml")
        self.assertEqual('<XMLFile of %r>' % (fobj,), repr(XMLFile(fobj)))

        An L{XMLFile} with a file object returns a useful repr().
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/test/test_template.py