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: ['6475', 'h', 's', 'V', 'h', 'h', 'Y', 'l', 'Q', '7899', 'm', '1287', '1245', '549', '9101', 'k', 'E', 'h', '8499', 'n']

6475, 8, 19, 22, 8, 8, 25, 12, 17, 7899, 13, 1287, 1245, 549, 9101, 11, 5, 8, 8499, 14