| 1153 | __str__ = None |
| 1154 | |
| 1155 | class N: |
| 1156 | def __init__(self, x): |
| 1157 | self.x = x |
| 1158 | def __repr__(self): |
| 1159 | return 'N(' + self.x + ')' |
| 1160 | __format__ = None |
| 1161 | |
| 1162 | self.assertEqual(''.format(), '') |
| 1163 | self.assertEqual('abc'.format(), 'abc') |