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Date: Mon, 13 Jan 2014 10:00:46 +0100
From: Laszlo Nagy <gandalf@shopzeus.com>
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Subject: Re: L[:]
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> Unless L is aliased, this is silly code.
There is another use case. If you intend to modify a list within a for 
loop that goes over the same list, then you need to iterate over a copy. 
And this cannot be called an "alias" because it has no name:

for idx,item in enumerate(L[:]):
    # do something with L here, including modification



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