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: ['6489', '7255', '9799', 'z', '4271', '6679', 'r', 'i', 'w', '6751']

6489, 7255, 9799, 26, 4271, 6679, 18, 9, 23, 6751