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: ['6447', 'V', 'Z', 'c', 'X', '5251', 'P', 'L', '2895', 'E', 'Y', 'v', 'n', 'e', '1201', '5533', '579', '7791', '6145', 'U', 'X', 'B', '2967', 'i', 'X', 'p', '4511', 'G', '5683', '7909', '9991', '4629', 'k', 'A', '6445', 'y', '699', '8723', '6481', '39']

6447, 22, 26, 3, 24, 5251, 16, 12, 2895, 5, 25, 22, 14, 5, 1201, 5533, 579, 7791, 6145, 21, 24, 2, 2967, 9, 24, 16, 4511, 7, 5683, 7909, 9991, 4629, 11, 1, 6445, 25, 699, 8723, 6481, 39