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Date: Sat, 26 Nov 2011 23:38:26 +0100
From: Alexander Kapps <alex.kapps@web.de>
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Subject: Re: Pragmatics of the standard is() function
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:16266

On 26.11.2011 22:20, candide wrote:

You already got answers for the "is" vs. "==" difference. I'd like 
to add the following.

> In which cases should we use the is() function ?

"is" is not a function, It's an operator, just like == or +.

> is() function makes comparaison of (abstract representation of)
> adresses of objects in memory.

That's an implementation detail. CPython (and maybe others) 
implement "is" in terms of memory addresses. Other implementations 
might use an object ID number or whatever else.