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: ['O', '9489', 'E', 'x', 'D', '1909', '3275', 'e', '4425', '3387', '9191', '1433', '2777', 'p', '885', 'r', 'p', 'W', '5767', 'C', '6699', 'w', 'k', 'a', '4971', '6979', '8711', 't', '4423', 'r', '2735', 'p']

15, 9489, 5, 24, 4, 1909, 3275, 5, 4425, 3387, 9191, 1433, 2777, 16, 885, 18, 16, 23, 5767, 3, 6699, 23, 11, 1, 4971, 6979, 8711, 20, 4423, 18, 2735, 16