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: ['j', 's', '4789', '3123', '2967', 'I', '45', 'r', 'n', 'Y', 'R', 'a', '6379', '1771']

10, 19, 4789, 3123, 2967, 9, 45, 18, 14, 25, 18, 1, 6379, 1771