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: ['4129', '6115', '7797', '2651', '4217', '3965', '8775', '887', 'b', '7413', 'r', 'T', '7731', 'p', 'f', 'N', 'M', '287', '1511', 'P', 'S', 'Z', '3379', 'a', 'n', '6269', 'f', 'u', 'B', '3053', '5293', '9065', 'f', 'E', 'I', '6435', 'y', '8791', '411', '8591']

4129, 6115, 7797, 2651, 4217, 3965, 8775, 887, 2, 7413, 18, 20, 7731, 16, 6, 14, 13, 287, 1511, 16, 19, 26, 3379, 1, 14, 6269, 6, 21, 2, 3053, 5293, 9065, 6, 5, 9, 6435, 25, 8791, 411, 8591