[docs] [issue1283110] Give __len__() advice for "don't know"

[Todd Rovito]

Changes by Todd Rovito <rovitotv at gmail.com>:


Removed file: http://bugs.python.org/file27605/DataModel__len__.patch

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue1283110>
_______________________________________