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: ['599', '2775', '3251', '2125', '2863', '3275', 'T', '5137', 'a', 'E']

599, 2775, 3251, 2125, 2863, 3275, 20, 5137, 1, 5