medium1_shallow_deep3.md

l1 = [[10,20,30], 1, 2, 3]# a list with another list at index 0
l2 = list(l1)             # create a copy

l1.append(4)              # append to list l1
l1[0].append(40)          # modify the inner list of l1

print(l1)
print(l2)

Output
[[10, 20, 30, 40], 1, 2, 3, 4]
[[10, 20, 30, 40], 1, 2, 3]