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: ['4331', '4445', 'm', '6813', '3507', 'k', 'm', 'O', '6765', 's', 'X', '5685', '8321', 'U', 'D', 'N', '6835', 'K']

4331, 4445, 13, 6813, 3507, 11, 13, 15, 6765, 19, 24, 5685, 8321, 21, 4, 14, 6835, 11