Python 3.7.0 (v3.7.0:1bf9cc5093, Jun 26 2018, 23:26:24) 
[Clang 6.0 (clang-600.0.57)] on darwin
Type "copyright", "credits" or "license()" for more information.
>>> s = "hello"
>>> a = [ 123, 12.5, True, "A"]
>>> s
'hello'
>>> a
[123, 12.5, True, 'A']
>>> b = [ 23, [34, 35], 2.3]
>>> b
[23, [34, 35], 2.3]
>>> len(b)
3
>>> len(a)
4
>>> a[0]
123
>>> b[0]
23
>>> a[1]
12.5
>>> b[1]
[34, 35]
>>> b[2]
2.3
>>> b
[23, [34, 35], 2.3]
>>> b[1][0]
34
>>>