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: ['W', 'h', '5709', '8973', 'h', '655', 'd', 'y', '6873', 'Q', 'b']

23, 8, 5709, 8973, 8, 655, 4, 25, 6873, 17, 2