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: ['4813', '3941', 'F', 's', '4569', 'b', '9741', '9711', 'H', 'N', 'R', 'm', '2615']

4813, 3941, 6, 19, 4569, 2, 9741, 9711, 8, 14, 18, 13, 2615