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: ['e', 'M', 'G', 'c', 'c', '6781', 'O', 'D']

5, 13, 7, 3, 3, 6781, 15, 4