Definition: In this task, you are given inputs i,j, and A, where i and j are integers and A is a list. You need to concatenate all elements of A from the ith element to the jth element, and print the resultant string. i and j will be non-negative, and will always have a value less than the length of A. i will always be less than j.
Input: 5, 21, ['2709', '8235', '9703', 'I', '6391', 'H', '8711', '7651', '7843', '3149', 'B', '6489', 'h', '7525', '6799', 'i', 'b', 'M', 'Y', 's', 't', '4849']

6391H8711765178433149B6489h75256799ibMYst