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: ['N', 'D', 'H', '4359', '7983', 'i', '6733', 'x', 's', '4525', '8951', '6959', 'f', '2749', '8001', '3749', '2431', 'S', 'D', 'F']

14, 4, 8, 4359, 7983, 9, 6733, 24, 19, 4525, 8951, 6959, 6, 2749, 8001, 3749, 2431, 19, 4, 6