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: ['L', '3587', 'v', '8759', '2127', '9501', 't', '5111', 'S', 'A', '5589', 'p', 'E', 'b', '7017', 'K']

12, 3587, 22, 8759, 2127, 9501, 20, 5111, 19, 1, 5589, 16, 5, 2, 7017, 11