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: ['S', 'T', 'F', 'x', 'u', 'c', 'T', '9989', '6835', '2489', 'y', '315', 'h', 'O', 'F', '7055', '6027', '2615', '2413', '9309', '999', 'Z', '7959', 'z']

19, 20, 6, 24, 21, 3, 20, 9989, 6835, 2489, 25, 315, 8, 15, 6, 7055, 6027, 2615, 2413, 9309, 999, 26, 7959, 26