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: ['149', '9999', '2743', 'L', '1399', '3895', 'V', '5033', '6769', 'h', 'f', 'J', 's', 'T', 'n', '8817', 'L', 'Q', 'B', 'U', 'v', '8563', '9487', '9423', 's', '3533', '5071', '2383', 'U', 'g', 'H', 'k', '5143', '2075', '2231', '9313', '5221']

149, 9999, 2743, 12, 1399, 3895, 22, 5033, 6769, 8, 6, 10, 19, 20, 14, 8817, 12, 17, 2, 21, 22, 8563, 9487, 9423, 19, 3533, 5071, 2383, 21, 7, 8, 11, 5143, 2075, 2231, 9313, 5221