list = ['a', 20, 40, ['b', 1.10, 12]];
print(list[2])
40
print(list[3][1])
1.1
print(list[-1])
['b', 1.1, 12]
print(list[1:3])
[20, 40]
print(list[:3])
['a', 20, 40]
print(list[2:])
[40, ['b', 1.1, 12]]
list[3] = 33
print(list)
['a', 20, 40, 33]
arr = [[[1,2]]]
print(arr[0][0][0])
1