Help with challenge problem

Question

Could someone explain what the s variable means?
https://imgur.com/a/tjq8Zgv

Answer 1

Storing the value of '{2}{1}{0}'.format(i[0], i[1], i[2]) in s

'{2}{1}{0}'.format(i[0], i[1], i[2])
= '{2}{1}{0}'.format(1, 2, 3)
= 321

Learn about format() function

Answer 2

Hi! You can google and read about it. Look up: Python String format() method.