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', '8401', '3129', 'B', 'd', '8477', 'R', 'V', 'o', '6799', '9913', '7977', 'm']

24, 8401, 3129, 2, 4, 8477, 18, 22, 15, 6799, 9913, 7977, 13