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: ['6503', '771', '2879', 'o', '7335', 'g', 'm', 'X', 'J', 'r', '9959', '1635', 'T', 's', '5855', 'N', 'r', 'G', 'H', 'q', '7509', 'h', 'd', '7547', 'D', '1275', 'k', 'F', 'b', 'g', 'n', 'h', '3837']

6503, 771, 2879, 15, 7335, 7, 13, 24, 10, 18, 9959, 1635, 20, 19, 5855, 14, 18, 7, 8, 17, 7509, 8, 4, 7547, 4, 1275, 11, 6, 2, 7, 14, 8, 3837