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: ['n', '3439', '7577', '3569', '61', 'U', '5317', '8511', '6731', 'T', 'G', 'v', '3623', '4673', '1881', '2531', '9501', '2691', '6303', 'X', '6975', '4635']

14, 3439, 7577, 3569, 61, 21, 5317, 8511, 6731, 20, 7, 22, 3623, 4673, 1881, 2531, 9501, 2691, 6303, 24, 6975, 4635