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: ['6173', '9835', 'Q', 'K', 'U', '5813', 'l', 'X', '2431', '9669', '8645', 'l', '4361', '8801', '2977', '9699', 'N', 'O', '8967', '3739']

6173, 9835, 17, 11, 21, 5813, 12, 24, 2431, 9669, 8645, 12, 4361, 8801, 2977, 9699, 14, 15, 8967, 3739