Yes, there are four List Objects.
They are color-coded here:
The outermost list (colored yellow) has only one item, A; that list
item is made of a few characters ("First Exercise") and another list object
(colored magenta).
The magenta list has three items, labelled 1, 2, & 3.
The first and third list items are both made of some characters and yet
other list objects.
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