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: ['r', 'I', 'H', 'K', 'n', 'p', 's', 'R', '5771', 'P', '833', 'k', '4339', 'c', '7993', 'N', '4347', '87', 'J', '517', 'n', 'Y', 'p', '9893', 'J']

18, 9, 8, 11, 14, 16, 19, 18, 5771, 16, 833, 11, 4339, 3, 7993, 14, 4347, 87, 10, 517, 14, 25, 16, 9893, 10