All possible permutations of a set of lists in Python

Posted by Ian Davis on Stack Overflow See other posts from Stack Overflow or by Ian Davis
Published on 2010-05-17T22:05:15Z Indexed on 2010/05/17 22:10 UTC
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permutations

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In Python I have a list of n lists, each with a variable number of elements. How can I create a single list containing all the possible permutations:

For example

[ [ a, b, c], [d], [e, f] ]

I want

[ [a, d, e] , [a, d, f], [b, d, e], [b, d, f], [c, d, e], [c, d, f] ]

Note I don't know n in advance. I thought itertools.product would be the right approach but it requires me to know the number of arguments in advance

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