# find array product like http://www.python.org/dev/peps/pep-0211/ 
# which means
# [1,2,3]@[4,5]@[6,7] = [1,4,6],[1,4,7],[1,5,6],[1,5,7],[2,4,6]... and so on
def aprod(*arg):
    numarg = len(arg)
    lenarray = map(len,arg)
    finallen = reduce(lambda x,y:x*y,lenarray)
    divisor = map(lambda i: reduce(lambda x,y:x*y,lenarray[i+1:],1),xrange(numarg))
    index = [map(lambda n,l: (x/n)%l,divisor,lenarray) for x in xrange(finallen)]
    #if you just want index for loop you can return index here
    return map(lambda ia:map(lambda a,i: a[i],arg,ia),index)

print aprod([1,2,3],[2,4,5,6],[7,8,9])