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', 's', '561', 'p', '9509', 'X', 'W', '2247', '4705', '9153', 'F', 'P', '2459']

25, 19, 561, 16, 9509, 24, 23, 2247, 4705, 9153, 6, 16, 2459