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From: <paul.hermeneutic@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: "x == None" vs "x is None"
Date: Sun, 17 Jan 2016 11:01:11 -0700
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Xref: csiph.com comp.lang.python:101859

I prefer (x is None) and (x is not None).

This matches the SQL concept of NULL.

(X = NULL) is not valid since NULL is not a value and cannot be compared
with anything.