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: ['Z', '5557', 'X', 'M', '8271', '7699', '193', 'N', '5115', '8139', 'c']

26, 5557, 24, 13, 8271, 7699, 193, 14, 5115, 8139, 3