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, 21, ['W', 'J', '2095', 'w', '9229', '8629', 'v', '8733', 'a', '9171', '8971', 'c', 'v', '5951', '2381', '4557', 'l', 'o', '2397', '7717', 'l']

l77172397ol455723815951vc89719171a