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', 'z', '3309', '8597', 'l', '7501', '8257']

13, 26, 3309, 8597, 12, 7501, 8257