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: ['s', 'p', 'P', 's', '2649', 'K', '7977', 'B', 'B', 's', '1207', 'F', '3009', '7365', 'W', '1705']

19, 16, 16, 19, 2649, 11, 7977, 2, 2, 19, 1207, 6, 3009, 7365, 23, 1705