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: ['9263', 'c', 'B', '481', 'R', '6599', '1861', '5431', 'G', 'c', '8981', 'p', '3911', 'X', '5083', '2437', 'B', 'M']

9263, 3, 2, 481, 18, 6599, 1861, 5431, 7, 3, 8981, 16, 3911, 24, 5083, 2437, 2, 13