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: ['9639', '979', '2873', '2909', 'T', '9793', 's', 'p', '3811', 'r', '3567', '8815', 'y']

9639, 979, 2873, 2909, 20, 9793, 19, 16, 3811, 18, 3567, 8815, 25