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: ['5319', '6495', 'Y', '5057', 'p', '589', 'U', 'P', '879', 'B', 't', 'E', 'Y', '4287', 'g', 'h', '7655']

5319, 6495, 25, 5057, 16, 589, 21, 16, 879, 2, 20, 5, 25, 4287, 7, 8, 7655