Cartesian Product of two lists (itertools)

[Thorsten Kampe]

Hi,

is there a way to make itertools.product generate triples instead of 
pairs from two lists?

For example:
>>> list1 = [1, 2]; list2 = [4, 5]; list3 = [7, 8]
>>> from itertools import product
>>> list(product(list1, list2, list3))
[(1, 4, 7), (1, 4, 8), (1, 5, 7), (1, 5, 8), (2, 4, 7), (2, 4, 8), (2, 
5, 7), (2, 5, 8)]

so far so good... Now...
>>> list(product(product(list1, list2), list3))
[((1, 4), 7), ((1, 4), 8), ((1, 5), 7), ((1, 5), 8), ((2, 4), 7), ((2, 
4), 8), ((2, 5), 7), ((2, 5), 8)]

Oops, pairs of pairs instead triples. Not what I wanted.

What's the best way to pre-process the arguments to "itertools.product" 
or to post-process the result of "itertools.product" to get what I 
want?!

I have an older utility which I would like to replace with 
itertools.product. The old one uses a rather clumsy way to indicate that 
a triple was wanted:

def cartes(seq0, seq1, modus = 'pair'):
    """ return the Cartesian Product of two sequences """
    if   modus == 'pair':
        return [[item0, item1] for item0 in seq0 for item1 in seq1]
    elif modus == 'triple':
        return [item0 + [item1] for item0 in seq0 for item1 in seq1]


Thorsten