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From: Terry Reedy <tjreedy@udel.edu>
Subject: Re: What the Pythons docs means by "container" ?
Date: Wed, 18 Feb 2015 15:04:12 -0500
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Xref: csiph.com comp.lang.python:85816

On 2/18/2015 2:43 PM, Ethan Furman wrote:

> Whether a "contained" object exists before it is accessed is irrelevant, is an implementation detail, and is a level of
> optimization.

Is in not irrelevant in that virtual collections can be infinite.

-- 
Terry Jan Reedy