Practice Code Assessment

So basically, I am practicing for a upcoming code assessment on Thursday, which of course it can't be leaked and have no intention on doing so, but there are practice code assessment tests that I can practice on. This is the question of one of the one's I was working on: ```Consider two following representations of a non-negative integer: A simple decimal integer, constructed of a non-empty sequence of digits from 0 to 9; An integer with at least one digit in a base from 2 to 16 (inclusive), enclosed between # characters, and preceded by the base, which can only be a number between 2 and 16 in the first representation. For digits from 10 to 15 characters a, b, ..., f and A, B, ..., F are used. Additionally, both representations may contain underscore (_) characters; they are used only as separators for improving legibility of numbers and can be ignored while processing a number. Your task is to determine whether the given string is a valid integer representation.``` And I will post the code below cause it is long. What I care about is that if I understand the question correctly and to the best of my knowledge.