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: ['C', 'U', '1707', 'I', '6531', '269', '8301', '6275', 'n', 'x', 'y']

3, 21, 1707, 9, 6531, 269, 8301, 6275, 14, 24, 25