Instructions: 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.
Input: 18, 21, ['3067', '5393', 'e', '2071', '3485', 'U', 'v', '935', 'w', 'Z', '8981', '8389', '4769', 'q', 'a', 'r', 'j', 'r', 'C', '7143', 'G']
Output:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
G3417Cr