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: ['4639', 'Q', 'K', 'k', '5807', 'I', '2571', '9013', 't', '9289', 'I', 'v', '21', '6181', 'X', 'p', '7919', '1325', 'l', '5031', '9695']

4639, 17, 11, 11, 5807, 9, 2571, 9013, 20, 9289, 9, 22, 21, 6181, 24, 16, 7919, 1325, 12, 5031, 9695