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: ['5273', '5539', '993', '8787', 'r', '1413', '3931', 'z', 'g', 'c', 'D', '9909', 'a', 'V', '1657', '2823', 'e', 't', 't', 'b', '3771', '1177', 'f', '855']

5273, 5539, 993, 8787, 18, 1413, 3931, 26, 7, 3, 4, 9909, 1, 22, 1657, 2823, 5, 20, 20, 2, 3771, 1177, 6, 855