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: ['X', 'o', 's', 'U', '7307', 'l', 'z', 's', 'Q', 'B', '7921', 'j', 'U', '2557', 'g', '4129', '6101', '6241']

24, 15, 19, 21, 7307, 12, 26, 19, 17, 2, 7921, 10, 21, 2557, 7, 4129, 6101, 6241