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: ['l', '407', 'Y', '1975', '6315', 'V', '2341', 'r', 'e', 'Q', 'c', 'V', '5289', 'a', '821', '7761', 'k', 'q', 'S', 'l', 'H', '7529', 'e', '3077', '2811', '2625', 'o', 'c', '4841', 'e', 'D', '6615', '2459', 'N', '9973', '9443', 'g', '4327', '7185', 'O']

12, 407, 25, 1975, 6315, 22, 2341, 18, 5, 17, 3, 22, 5289, 1, 821, 7761, 11, 17, 19, 12, 8, 7529, 5, 3077, 2811, 2625, 15, 3, 4841, 5, 4, 6615, 2459, 14, 9973, 9443, 7, 4327, 7185, 15