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: ['n', '6321', 'k', '3407', 'E', 'q', '4575', '4149', '6435', 'Q', '2587', 'S', '7657', 'P', 'O', '9573']

14, 6321, 11, 3407, 5, 17, 4575, 4149, 6435, 17, 2587, 19, 7657, 16, 15, 9573