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: ['i', 'u', '9931', 'q', 'q', 'B', 'C', '9109', 't']

9, 21, 9931, 17, 17, 2, 3, 9109, 20