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: ['6913', '1029', 'v', 'k', '5873', 'B', 'c', '1779', '5413', 'D']

6913, 1029, 22, 11, 5873, 2, 3, 1779, 5413, 4