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: ['P', 'I', 'Q', '2031', 'C', 'O', '7557', 'R', '3881', '3209', '1561', '301', '2103', '7995', '1609', '1717', '5447', '9717', '9371', '1539', '4375', '251']

16, 9, 17, 2031, 3, 15, 7557, 18, 3881, 3209, 1561, 301, 2103, 7995, 1609, 1717, 5447, 9717, 9371, 1539, 4375, 251