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: ['v', '4609', '6879', 'm', 'O', 'c', '7531', 'B', '9575']

22, 4609, 6879, 13, 15, 3, 7531, 2, 9575