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: ['O', '3581', '7579', 'G', '1947', '6215', '1127', 'Y', '9821', 't', '1919', '1581', 'h', 'J', 'J']

15, 3581, 7579, 7, 1947, 6215, 1127, 25, 9821, 20, 1919, 1581, 8, 10, 10