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', 't', '3747', 'w', '6737', '7921', '9029']

23, 20, 3747, 23, 6737, 7921, 9029