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: ['2495', 'b', 'O', '9923', 'k', 'k', 'b', 'h', 'U', '5907', 'E', 'g', 't', 'o', 'f']

2495, 2, 15, 9923, 11, 11, 2, 8, 21, 5907, 5, 7, 20, 15, 6