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: ['F', 'B', '9053', 'L', '2533', 'g', 'X', '5247', '2073', '6907', '4887', 'B', 'y', '5715', '3257', 'S', '8525', 'P', '8613', '6291', 'S']

6, 2, 9053, 12, 2533, 7, 24, 5247, 2073, 6907, 4887, 2, 25, 5715, 3257, 19, 8525, 16, 8613, 6291, 19