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: ['4459', 'A', 'M', '8621', '4247', '2255']

4459, 1, 13, 8621, 4247, 2255