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: ['U', 'C', '7173', 'r', 'Z', 'e', '4057', '5191', 'k', '73', '9335', '6143', '8871', '6023', '5765', 'O', '5379', '5269', '9935', 'K', 'V', '7561', 'j', 'R', 'o', '9207', 'F', '7169', '9941', 'm', 'J', '4203', 'k', 'B', 'G']

21, 3, 7173, 18, 26, 5, 4057, 5191, 11, 73, 9335, 6143, 8871, 6023, 5765, 15, 5379, 5269, 9935, 11, 22, 7561, 10, 18, 15, 9207, 6, 7169, 9941, 13, 10, 4203, 11, 2, 7