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: ['6587', 'h', 'D', 'c', '3925', 'x', '5149', '2809', '8727', 'b', 'n', '6175', '1083', 'K', 'Z', '5489', '3097', '7113', '4913', 'L', 'q', '4265', '429', 'k', 'x', 't', 'i', 's', '7163', '6371', 'D']

6587, 8, 4, 3, 3925, 24, 5149, 2809, 8727, 2, 14, 6175, 1083, 11, 26, 5489, 3097, 7113, 4913, 12, 17, 4265, 429, 11, 24, 20, 9, 19, 7163, 6371, 4