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', 'u', 'O', '4173', 'l', 'r', 'b', 'v', '1157', 'h', 'b', '2321', 'I', 'O', 'y', '2159', '8293', 'R', 'G', 'g']

18, 21, 15, 4173, 12, 18, 2, 22, 1157, 8, 2, 2321, 9, 15, 25, 2159, 8293, 18, 7, 7