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: ['6423', '4225', 'N', 'B', 'X', 'O', 'T', 'S', 'N', '6749', 'D', 'u', '6495', '8621', 'Q', 'M', '8293', 'a', '5991', 'S', 'x', 'h', 'V', '4351', '7097', 'F', 'n', '2159', '231', '6377', '8823']

6423, 4225, 14, 2, 24, 15, 20, 19, 14, 6749, 4, 21, 6495, 8621, 17, 13, 8293, 1, 5991, 19, 24, 8, 22, 4351, 7097, 6, 14, 2159, 231, 6377, 8823