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: ['7569', '8021', '2063', '9539', 'K', 'j', 'Z', '9723', 'e', 'd', '287']

7569, 8021, 2063, 9539, 11, 10, 26, 9723, 5, 4, 287