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 find all elements of A from the ith element to the jth element, reverse the order in which they occur, and then concatenate them to output 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. Perform the operations in order, i.e., do not concatenate the elements and then reverse the string.
Input: 19, 20, ['j', 'h', '2663', 'x', '3651', '6291', '6033', 'r', '3325', 'c', '5857', 'c', 'j', '5007', 'E', 'q', 'b', '3473', 'f', '4273']

4273f