Do you have real-world use cases for map's None fill-in feature?

[Fredrik Lundh]

Szabolcs Nagy wrote:

> there are iterators which has length:
> >>> i = iter([1,2,3])
> >>> len(i)
> 3

that's a bug, which has been fixed in 2.5:

Python 2.5a0 (#5, Dec 14 2005, 22:28:52)
Type "help", "copyright", "credits" or "license" for more information.
>>> i = iter([1, 2, 3])
>>> len(i)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: len() of unsized object

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