In this task, you are given inputs 'i', 'j', and A, where 'i' and 'j' are integers and A is a list. A list is shown by two brackets and comma-separated numbers and characters inside, like ['1', '12', 'l']. You need to concatenate all elements of A from the ith element to the jth element, and then reverse the resulting 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 reverse first and then concatenate.
21, 21, ['e', '8675', '6937', 'o', '2985', '5179', '323', 'S', 'H', '2985', 'H', '6521', '4311', 'H', 'I', '2179', '4653', '7787', 'P', '429', '9883', '3897', '6837', 'y', 'Q', 'L']