2d list to 3d list in python

Question

Suppose I have two lists given by,

list1 = [[2,3,1,3],[2,4,6,2]]

list2 = [[1,2,3,4],[4,3,2,1]]

How would one convert to a 3d list?

So that to access list1, one would:

list3[0] = list1

list3[1] = list2

where print list3 would provide:

[[[2,3,1,3],[2,4,6,2]],[[1,2,3,4],[4,3,2,1]]]

I have tried adding, but that doesn't seem to work.

Answer 1

list1 = [[2,3,1,3],[2,4,6,2]]
list2 = [[1,2,3,4],[4,3,2,1]]
list3 = [list1, list2]

Answer 2

You actually need to deepcopy the tuples/lists to avoid creating references:

list1 = [2,3,1,3],[2,4,6,2]

list2 = [1,2,3,4],[4,3,2,1]

from copy import deepcopy

l3 = list(map(list, map(deepcopy,(list1, list2))))


print(l3[0])
print(l3[1])
[[2, 3, 1, 3], [2, 4, 6, 2]]
[[1, 2, 3, 4], [4, 3, 2, 1]]

If you have lists not actually tuples you can remove the outer map:

l3 = list(map(deepcopy,(list1, list2)))