[docs] [issue28785] Clarify the behavior of NotImplemented

[Max]

New submission from Max:

Currently, there's no clear statement as to what exactly the fallback is in case `__eq__` returns `NotImplemented`.  It would be good to clarify the behavior of `NotImplemented`; at least for `__eq__`, but perhaps also other rich comparison methods. For example: "When `NotImplemented` is returned from a rich comparison method, the interpreter behaves as if the rich comparison method was not defined in the first place." See http://stackoverflow.com/questions/40780004/returning-notimplemented-from-eq for more discussion.

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assignee: docs at python
components: Documentation
messages: 281616
nosy: docs at python, max
priority: normal
severity: normal
status: open
title: Clarify the behavior of NotImplemented
type: enhancement
versions: Python 3.6

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue28785>
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