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: 9, 20, ['531', 'I', 'p', 'j', 'e', 'u', '423', '715', '7971', '2331', 'n', '3017', 'l', 'L', 'u', '9427', 'o', '1811', '2757', '877', 'f', 'x', 's', 'N', 'W']

87727571811o9427uLl3017n23317971