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: ['A', '7853', '5879', 'M', 'V', '9541', 'l', 'f', 'y', '9579', '9515', 'J', '7917', 'Z', '9747', '5001', '6237', '6563', 's', '3763']

1, 7853, 5879, 13, 22, 9541, 12, 6, 25, 9579, 9515, 10, 7917, 26, 9747, 5001, 6237, 6563, 19, 3763