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: ['403', 'C', 'G', 'M', 'a', '6861', 'd', 'v', 'K', 'Z', '8349', '1213', '2615', 'y', 'E', 'p', 'D', '4471', '2733', 'W', '5713', 'A', '781', 'p', 'B']

403, 3, 7, 13, 1, 6861, 4, 22, 11, 26, 8349, 1213, 2615, 25, 5, 16, 4, 4471, 2733, 23, 5713, 1, 781, 16, 2