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: ['Y', 'A', '9149', '5801', '2287', '8075', '3425', '5353', '6359', '3423', 'z', '1187', 'I', '2389', 'S']

25, 1, 9149, 5801, 2287, 8075, 3425, 5353, 6359, 3423, 26, 1187, 9, 2389, 19