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: ['P', '7635', '2103', '6953', 'e', '5345', 'm', 'r', '8045', 'N', '4637', '4331', 'R', '7575', 'Y', '2591', '3485', '207', '2915', '553', 'l', 'V']

16, 7635, 2103, 6953, 5, 5345, 13, 18, 8045, 14, 4637, 4331, 18, 7575, 25, 2591, 3485, 207, 2915, 553, 12, 22