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: ['m', '7797', '5091', '1749', '2769', '7299', '135', 'O', '997', 'e', '6351', '7637', '3203', '3789', 'p', 'W', '7301', 'L', '3143', '5213', 'A']

13, 7797, 5091, 1749, 2769, 7299, 135, 15, 997, 5, 6351, 7637, 3203, 3789, 16, 23, 7301, 12, 3143, 5213, 1