Definition: In this task, you are given an input list A. You need to convert all the alphabets in the list with a number representing their position in the English alphabet. E.g., replace A by 1, B by 2, a by 1, b by 2, and so on.
Input: ['L', '8459', 'f', '4507', 'W', 'B', 'r', '4173', '91', 'X', 'A', '6555', 'l', '4541', '1565', 'F', 'Z', 'C', '2935', 'r', 'o', 'c', 'X']

12, 8459, 6, 4507, 23, 2, 18, 4173, 91, 24, 1, 6555, 12, 4541, 1565, 6, 26, 3, 2935, 18, 15, 3, 24