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: ['663', '9795', 'M', '3199', '225', 'Y', '3789', 'B', 'c', 'T', '4427', '8729', '7849', '4855', '8057']

663, 9795, 13, 3199, 225, 25, 3789, 2, 3, 20, 4427, 8729, 7849, 4855, 8057