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: ['U', '1587', 'L', 'Y', 'Z', '1111', '8361', '4545', '7265', '5779', 'a', 'B', 'X', 'Q', 'X', 'f', '6199', 'g', '8111', 'g', '2527', '5435', 'z', 'v', 'u', 'M', '4369', '2891', 'Z', 'p', 'n', 'H', '9069', '5001']

21, 1587, 12, 25, 26, 1111, 8361, 4545, 7265, 5779, 1, 2, 24, 17, 24, 6, 6199, 7, 8111, 7, 2527, 5435, 26, 22, 21, 13, 4369, 2891, 26, 16, 14, 8, 9069, 5001