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: ['v', 'z', 'B', 'N', '273', 'g', 'f', 'l', '3189', 'D', '5861', '5693', 'C', '8703', '2543', 'D']

22, 26, 2, 14, 273, 7, 6, 12, 3189, 4, 5861, 5693, 3, 8703, 2543, 4