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: ['7943', '8553', 'f', 'R', '3101', 'J', 'Y', 'y', '8909', 'n', '8251', 'p', 'd', 'a', '2359', 'A', '2745', 'Y', '1071']

7943, 8553, 6, 18, 3101, 10, 25, 25, 8909, 14, 8251, 16, 4, 1, 2359, 1, 2745, 25, 1071