New submission from Joseph Fall: This report is to re-raise an old issue from 2009: http://bugs.python.org/issue5370 Although that issue is marked as "fixed", I disagree that it was ever "fixed", and spent an evil day tracking it down. Use Case: - take two 3rd party packages: django and django-crispy-forms - django, deep in its inner-workings, uses Pickle - django-cripsy-forms implements the _getattr__ method in one of it's classes - when you put the two together such that django pickles a form, the python interpreter goes into a tailspin in very sinister and hard-to-track-down ways (different behaviour in 2.5, 2.6, 2.7, as noted in issue5370, which includes a simple test case) The "resolution" for issue5370 was to add some documentation to Pickle. But I would argue this is insufficient - the implementer of django-crispy-forms would have no reason to ever look at the Pickle docs, and so is very likely to implement this bug (which s/he did). Perhaps, if this issue cannot be resolved in code, as suggested by gagenellina back in 2009, at least some documentation could be added to __getattr__ (and others) warning that these methods could potentially be called before __init__ (similar to the documentation added to Pickle)? I'd be happy to draft a small bit of documentation for this, although if someone can think of a way to simply resolve this in Pickle so it does not cause the issue in the first place, that seems to me ideal. A test case is included with issue5370 ---------- assignee: docs@python components: Documentation, Library (Lib) messages: 172993 nosy: docs@python, powderflask priority: normal severity: normal status: open title: Pickle and __getattr__ type: behavior versions: Python 2.6, Python 2.7 _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue16242> _______________________________________