| 202 | # (F) subclass sets __missing__ instance variable (no effect) |
| 203 | # (G) subclass doesn't define __missing__ at all |
| 204 | class D(collections.UserDict): |
| 205 | def __missing__(self, key): |
| 206 | return 42 |
| 207 | d = D({1: 2, 3: 4}) |
| 208 | self.assertEqual(d[1], 2) |
| 209 | self.assertEqual(d[3], 4) |