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: ['h', 'T', '3899', '637', '9203', 'l', '1559', 'F', '5453', 'l', '1897', '5407', 'D', '905', 'z']

8, 20, 3899, 637, 9203, 12, 1559, 6, 5453, 12, 1897, 5407, 4, 905, 26