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.
20, 27, ['7489', 's', 'A', '627', 'W', 'I', 'O', 'f', '8759', '7835', '8055', '515', 'b', '1687', 'o', '9445', 'z', 'R', 'Z', '839', '9091', '2637', 'M', '3563', '3487', '2779', 'g']