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: ['6131', 'T', 'G', '1653', 'W', '1569', '1875', 'k', 'K', '1503', '175', '3813', '9501', 'l', 'a', 'w', '7769', 'h', 'E', '9877', 'R']

6131, 20, 7, 1653, 23, 1569, 1875, 11, 11, 1503, 175, 3813, 9501, 12, 1, 23, 7769, 8, 5, 9877, 18