I have a list of lists say

[[2, 4, 6], [2, 6, 10], [2, 12, 22], [4, 6, 8], [4, 8, 12], [6, 8, 10], [8, 10, 12], [8, 15, 22], [10, 11, 12]]

How do I generate a combination of the lists for a given length?

For example if the given length is 3

Then I need all combinations of 3 list element scenarios from the given list of list.

Example :

[2, 4, 6], [2, 6, 10], [2, 12, 22]

or

[2, 4, 6], [8, 10, 12], [10, 11, 12]
...
... and so forth

and if the given length is 2 then it should be like

[2, 4, 6], [2, 6, 10]

or

[6, 8, 10], [8, 10, 12]
...
... and so forth

I dont want a permutation of elements inside the lists but I want a permutation of the lists itself.

There are two options here. The first is to use itertools.permutations. This will give you every permutation (i.e: [1,2] and [2,1] would not be the same)

import itertoolslists = [[2, 4, 6], [2, 6, 10], [2, 12, 22], [4, 6, 8], [4, 8, 12], [6, 8, 10], [8, 10, 12], [8, 15, 22], [10, 11, 12]]
n = 3for perm in itertools.permutations(lists, n):print(perm)

If you want completely unique groupings, with no duplicates , use itertools.combinations (i.e: [1,2] and [2,1] would be the same).

for comb in itertools.combinations(lists, n):print(comb)