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: ['q', '8519', 'T', '6859', '5397', '3753', '2057', '5723', 'T', 'R', '7807', 'h', '9507', '7865', '8513', '2309', 'j', 'n', 'P', 'a', '8971', 'U', '7927', '875', '3315', 'E', 't']

17, 8519, 20, 6859, 5397, 3753, 2057, 5723, 20, 18, 7807, 8, 9507, 7865, 8513, 2309, 10, 14, 16, 1, 8971, 21, 7927, 875, 3315, 5, 20