Instructions: 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: ['975', 'K', 's', '4859', '3367', 'l', '915']
Output:
975, 11, 19, 4859, 3367, 12, 915