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: ['2859', 'w', 'g', '3367', 'N', 'u', '5727', 'k', '5691', 'y', '2699', 'u', '6609', 'O']

2859, 23, 7, 3367, 14, 21, 5727, 11, 5691, 25, 2699, 21, 6609, 15