>  I have this list wich is made of tuples. I wish I could "flatten" 
>  this list, that is, to extract each element in the tuples and 
>  build a new flat list with it. 

Recursion is often used for this, there is an example 
function in my tutorial topic on recursion (using nested 
lists rather than tuples but it should work for either)

Alan G
Author of the Learn to Program web tutor
http://www.freenetpages.co.uk/hp/alan.gauld
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