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: ['5569', 'D', 'x', '4103', 'B', '6187', 'J', 'P', '9263']

5569, 4, 24, 4103, 2, 6187, 10, 16, 9263