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: ['J', '99', 'y', 'Y', '3187', '9889', '1265', '7097', 'B', '849', '9463', 'T', '2047', '6945', '6733', '7257', 'b', '4717', '1563', 'h', '9561', 'D', 'Z', '7605', 'U', '2603', '487', '5187', '5373', 'c', '343', 'a', 'x', 'u', '5681', 'I']

10, 99, 25, 25, 3187, 9889, 1265, 7097, 2, 849, 9463, 20, 2047, 6945, 6733, 7257, 2, 4717, 1563, 8, 9561, 4, 26, 7605, 21, 2603, 487, 5187, 5373, 3, 343, 1, 24, 21, 5681, 9