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: ['s', '6083', '2595', 'O', '1207', '851', 'x', 'P', 'S']

19, 6083, 2595, 15, 1207, 851, 24, 16, 19