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', '4549', 'u', 'G', '9057', '5987', '853', 'J', '3677', 'p', '3267', '1211', 'z']

8, 4549, 21, 7, 9057, 5987, 853, 10, 3677, 16, 3267, 1211, 26