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', '2507', 'E', 'E', '9329', 'c', 'P', '7923', 'i', '1', 'I', 'n', '9819', '5939', '5027', 'B', '1243', '257', '9735', '887', '2309', '8251']

3, 2507, 5, 5, 9329, 3, 16, 7923, 9, 1, 9, 14, 9819, 5939, 5027, 2, 1243, 257, 9735, 887, 2309, 8251