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: ['U', 'j', '317', 's', 'k', '5519', 'q', '7163', '3725', '5623', '6375', 'n', '1923', '9873', '1917', 'f', '8661', '6943']

21, 10, 317, 19, 11, 5519, 17, 7163, 3725, 5623, 6375, 14, 1923, 9873, 1917, 6, 8661, 6943