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: ['W', 'j', '6405', '1911', 'B', '7937', '3235', '9735', '4229', 'd', 's', 'o', 'F', '4991', 'M', '3341']

23, 10, 6405, 1911, 2, 7937, 3235, 9735, 4229, 4, 19, 15, 6, 4991, 13, 3341