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', '5895', 'q', '1663', '3223', 'h', 'F', 'W', '3167', 'e', '5759', '6963', '129', 'G', '9315', '7835', 'U', '8123', 'E']

18, 5895, 17, 1663, 3223, 8, 6, 23, 3167, 5, 5759, 6963, 129, 7, 9315, 7835, 21, 8123, 5