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[Paul Watson]

"Alex Martelli" <aleaxit at yahoo.com> wrote in message 
news:1h5760l.1e2eatkurdeo7N%aleaxit at yahoo.com...

> In today's implementations of Classic Python, yes.  In other equally
> valid implementations of the language, such as Jython, IronPython, or,
> for all we know, some future implementation of Classic, that may well
> not be the case.  Many, quite reasonably, dislike relying on a specific
> implementation's peculiarities, and prefer to write code that relies
> only on what the _language_ specs guarantee.

How could I identify when Python code does not close files and depends on 
the runtime to take care of this?  I want to know that the code will work 
well under other Python implementations and future implementations which may 
not have this provided.