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From: Terry Reedy <tjreedy@udel.edu>
Subject: Re: Dynamic variable creation from string
Date: Wed, 07 Dec 2011 19:27:43 -0500
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On 12/7/2011 7:03 PM, Steven D'Aprano wrote:
> On Wed, 07 Dec 2011 09:09:16 -0800, Massi wrote:
>
>> Is there a way to create three variables dynamically inside Sum in order
>> to re write the function like this?

I should have mentioned in my earlier response that 'variable' is a bit 
vague and misleading. Python has names bound to objects.

>> def Sum(D) :
>>      # Here some magic to create a,b,c from D
>>      return a+b+c
>
> No magic is needed.
>
> a, b, c = D['a'], D['b'], D['c']

This is not what most people mean by 'dynamically created variables'. 
The names are static, in the code, before the code is executed.
In 2.x, 'from x import *' dynamically creates local names that are not 
in the code that contains the import. Dynamically creating objects is 
what Python code does all the time.

-- 
Terry Jan Reedy