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: ['2255', '2807', 'U', '3477', 'x', '8931', 'w', 'B', 'g', '6547', '4751', 'n', '7337', 'k', '9253', '6557', 't', 'P', '8779']

2255, 2807, 21, 3477, 24, 8931, 23, 2, 7, 6547, 4751, 14, 7337, 11, 9253, 6557, 20, 16, 8779