def test_permissionsShorthand(self):
        """
        L{Permissions}'s shorthand string is the RWX shorthand string for its
        user permission bits, group permission bits, and other permission bits
        concatenated together, without a space.
        """
        for u in range(0, 8):
            for g in range(0, 8):
                for o in range(0, 8):
                    perm = filepath.Permissions(int("0o%d%d%d" % (u, g, o), 8))
                    self.assertEqual(perm.shorthand(),
                                      ''.join(x.shorthand() for x in (
                                          perm.user, perm.group, perm.other)))
        self.assertEqual(filepath.Permissions(0o770).shorthand(), "rwxrwx---")

        L{Permissions}'s shorthand string is the RWX shorthand string for its
        user permission bits, group permission bits, and other permission bits
        concatenated together, without a space.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_paths.py