One can use base python for this. The code needs a function to flatten lists of lists:
def flatten(B): # function needed for code below;
A = []
for i in B:
if type(i) == list: A.extend(i)
else: A.append(i)
return A
Then one can run:
L = [[1,2,3],[4,5,6],[7,8,9,10]]
outlist =[]; templist =[[]]
for sublist in L:
outlist = templist; templist = [[]]
for sitem in sublist:
for oitem in outlist:
newitem = [oitem]
if newitem == [[]]: newitem = [sitem]
else: newitem = [newitem[0], sitem]
templist.append(flatten(newitem))
outlist = list(filter(lambda x: len(x)==len(L), templist)) # remove some partial lists that also creep in;
print(outlist)
Output:
[[1, 4, 7], [2, 4, 7], [3, 4, 7],
[1, 5, 7], [2, 5, 7], [3, 5, 7],
[1, 6, 7], [2, 6, 7], [3, 6, 7],
[1, 4, 8], [2, 4, 8], [3, 4, 8],
[1, 5, 8], [2, 5, 8], [3, 5, 8],
[1, 6, 8], [2, 6, 8], [3, 6, 8],
[1, 4, 9], [2, 4, 9], [3, 4, 9],
[1, 5, 9], [2, 5, 9], [3, 5, 9],
[1, 6, 9], [2, 6, 9], [3, 6, 9],
[1, 4, 10], [2, 4, 10], [3, 4, 10],
[1, 5, 10], [2, 5, 10], [3, 5, 10],
[1, 6, 10], [2, 6, 10], [3, 6, 10]]