def roundtrip(self, f, s):
        st1 = f(s)
        t = st1.totuple()
        try:
            st2 = parser.sequence2st(t)
        except parser.ParserError as why:
            self.fail("could not roundtrip %r: %s" % (s, why))

        self.assertEqual(t, st2.totuple(),
                         "could not re-generate syntax tree")
dataset/ETHPy150Open amrdraz/kodr/app/brython/www/src/Lib/test/test_parser.py/RoundtripLegalSyntaxTestCase.roundtrip/original