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', 'y', 'Z', 'u', '5621', '825', 'w', '7839', 'B', 'Z', '5385', '9333']

9, 25, 26, 21, 5621, 825, 23, 7839, 2, 26, 5385, 9333