(self)
| 2913 | class madstring(str): |
| 2914 | _rev = None |
| 2915 | def rev(self): |
| 2916 | if self._rev is not None: |
| 2917 | return self._rev |
| 2918 | L = list(self) |
| 2919 | L.reverse() |
| 2920 | self._rev = self.__class__("".join(L)) |
| 2921 | return self._rev |
| 2922 | s = madstring("abcdefghijklmnopqrstuvwxyz") |
| 2923 | self.assertEqual(s, "abcdefghijklmnopqrstuvwxyz") |
| 2924 | self.assertEqual(s.rev(), madstring("zyxwvutsrqponmlkjihgfedcba")) |