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: ['a', '3841', 'K', '7813', '5911', 'H', '7969', '4155', '9451', '3595', 'z', '3499', '6533', 'Q', 'A', 'H', '8563', '5875', '5643', '1311']

1, 3841, 11, 7813, 5911, 8, 7969, 4155, 9451, 3595, 26, 3499, 6533, 17, 1, 8, 8563, 5875, 5643, 1311