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From: Chris Angelico <rosuav@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: one-element tuples [Was: Most probably a stupid question, but I still want to ask]
Date: Mon, 11 Apr 2016 10:38:33 +1000
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On Mon, Apr 11, 2016 at 10:33 AM, MRAB <python@mrabarnett.plus.com> wrote:
> For example, object are passed into a function thus:
>
>     f(x, y)
>
> (In reality, it's making a tuple and then passing that in.)

Actually that's not the case; certain syntactic constructs allow you
to specify multiple of something, without packaging them up into a
tuple. Function arguments and parameters are like this; otherwise
keyword arguments would have to be some kind of magic syntax in
tuples, instead of being a feature of function calls.

But there are plenty of situations where what you're describing _is_
the case, such as assigning multiple values to multiple targets:

# Package up y and x into a tuple
# Then unpack the tuple into two names
x, y = y, x

ChrisA