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: ['n', 'N', 'z', '7431', 'B', 's', '6857', '8609', '3921', '9313', '3501', '8665', 'R', 'p', '2779', '4251', '5377']

14, 14, 26, 7431, 2, 19, 6857, 8609, 3921, 9313, 3501, 8665, 18, 16, 2779, 4251, 5377