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: ['X', 'Y', 'X', '4081', '2783', 'z', '6973', 'j', '5677', 'r', 'b', '9243', 'W', 'g', 'I', 's', '7553']

24, 25, 24, 4081, 2783, 26, 6973, 10, 5677, 18, 2, 9243, 23, 7, 9, 19, 7553