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: ['p', '2253', 'j', '8787', 'g', '3283', 'X', 'F', 'W', '8997', '9929', '3625', 'X', '8429', 'c', '2007', 'S', '9275', '2491', 'G', 'l', 'j', 'u']

16, 2253, 10, 8787, 7, 3283, 24, 6, 23, 8997, 9929, 3625, 24, 8429, 3, 2007, 19, 9275, 2491, 7, 12, 10, 21