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: ['57', 'u', '9551', '4735', '2225', 'W', '9787', '1781', '9787', 'v', '1487', 'k', 'h', '5619', 'F', '2631', 'l', 'D', '5911', '4669', '6057', 'n', '3715', 'o', 'b', 'T', 'I', '2077', '2877']

57, 21, 9551, 4735, 2225, 23, 9787, 1781, 9787, 22, 1487, 11, 8, 5619, 6, 2631, 12, 4, 5911, 4669, 6057, 14, 3715, 15, 2, 20, 9, 2077, 2877