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: ['E', 'S', 'r', '8107', 'E', '4447', 'c', 'G', 'L', '3581', '9459', 'Y', 'Q']

5, 19, 18, 8107, 5, 4447, 3, 7, 12, 3581, 9459, 25, 17