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: ['9971', 'm', 'G', '4619', '4511', '3595', '1365', '2893', 'S', '8783', 'x']

9971, 13, 7, 4619, 4511, 3595, 1365, 2893, 19, 8783, 24