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: ['N', '2249', '6463', '2809', 'D', 'O', 'Z', '4209', 'x', 'r', 'G', '3013', '2885', '5225', 'c', 'p', 'H', 'j', 'K', 'L', 'Y', 'H', 'l', '721', '4731', '1275', 'P', '5575', 'x', 'g', '7881']

14, 2249, 6463, 2809, 4, 15, 26, 4209, 24, 18, 7, 3013, 2885, 5225, 3, 16, 8, 10, 11, 12, 25, 8, 12, 721, 4731, 1275, 16, 5575, 24, 7, 7881