| 609 | |
| 610 | |
| 611 | class _Empty: |
| 612 | def __call__(self, *args, **kw): |
| 613 | return self |
| 614 | |
| 615 | def __str__(self): |
| 616 | return '' |
| 617 | |
| 618 | def __repr__(self): |
| 619 | return 'Empty' |
| 620 | |
| 621 | def __unicode__(self): |
| 622 | return '' |
| 623 | |
| 624 | def __iter__(self): |
| 625 | return iter(()) |
| 626 | |
| 627 | def __bool__(self): |
| 628 | return False |
| 629 | |
| 630 | Empty = _Empty() |
| 631 | del _Empty |