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: ['6903', 'T', 'G', 'a', 'A', 'q', '9251', 'Q', 'M', 'O', 'd', '5691', 'z', 'b', '5537', '9203', '3265']

6903, 20, 7, 1, 1, 17, 9251, 17, 13, 15, 4, 5691, 26, 2, 5537, 9203, 3265