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: ['1257', '8707', '5833', 'B', '8749', '3351', '2797', 'J', 'W', 'i', 'F', 'F', '807', '4657', '3299', '7439', '7573', '4727', 'Z', '2965', '8771', 'I', 'W', 'Q', 't', 'n', 'E', '677', 'B', '5219', '4819']

1257, 8707, 5833, 2, 8749, 3351, 2797, 10, 23, 9, 6, 6, 807, 4657, 3299, 7439, 7573, 4727, 26, 2965, 8771, 9, 23, 17, 20, 14, 5, 677, 2, 5219, 4819