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Author ncoghlan
Recipients ncoghlan
Date 2013-01-01.03:21:36
SpamBayes Score -1.0
Marked as misclassified Yes
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Authors of __subclasshook__ methods need to decide between returning True, False and NotImplemented in various cases. Making that decision requires a clear understanding that the checks in ABCMeta.__subclasscheck__ occur in the following order:

- explicit registrations
- the __subclasshook__ call
- ordinary inheritance

So, returning False from __subclasshook__ allows you to override normal rules of inheritance, while returning NotImplemented lets normal inheritance rules apply. Explicit registrations take precedence regardless.
Date User Action Args
2013-01-01 03:21:37ncoghlansetrecipients: + ncoghlan
2013-01-01 03:21:37ncoghlansetmessageid: <>
2013-01-01 03:21:37ncoghlanlinkissue16831 messages
2013-01-01 03:21:36ncoghlancreate