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: ['5615', '1559', 'L', 'v', 'A', 'd', '5093', 'C', 'B', 'n', '9477', '8269', 'O', 'A', '6521', 'C', '5281', 'L', '6393', 'q', 'g', '8439', 'b', '5315', 'j', 'r', '2643', '9655', 'x', 'I', 'w']

5615, 1559, 12, 22, 1, 4, 5093, 3, 2, 14, 9477, 8269, 15, 1, 6521, 3, 5281, 12, 6393, 17, 7, 8439, 2, 5315, 10, 18, 2643, 9655, 24, 9, 23