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: ['7939', 'D', '2747', 'H', 'J', 'H', '6257', 'v', 'I', '6391', 't', 'y', '9607', 'T']

7939, 4, 2747, 8, 10, 8, 6257, 22, 9, 6391, 20, 25, 9607, 20