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: ['8613', 'L', '6071', '1223', 'z', '815', 'm', 'i', 'L']

8613, 12, 6071, 1223, 26, 815, 13, 9, 12