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: ['M', 'V', 'L', 'I', 'U', 'l', '4253', 'd', 'n']

13, 22, 12, 9, 21, 12, 4253, 4, 14