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: ['F', '6653', 'q', '6685', '9661', '9025', 'q', '8013', '7815', '2385', '3241', 'O', '2347', '4121', 'H', 'U', '3079', '9617', '7623', '4159', '9645']

6, 6653, 17, 6685, 9661, 9025, 17, 8013, 7815, 2385, 3241, 15, 2347, 4121, 8, 21, 3079, 9617, 7623, 4159, 9645