Definition: In this task, you are given an input list A comprising of numbers and alphabets. You need to extract and sort the unique alphabets in the list. The alphabets in the input list will only be in lowercase. Return -1 if there is no alphabet in the input list.
Input: ['g', '733', '5577', 'o', 's', 'y', 'b', 'k', '7159', '8465', 'g', '8135', 'm', '3541', 'd', 'h', 'r', '3025', '5805', '3817', 'p', 'y', '323', 'e', '2563', 'e', 'j', 'a', '521', '8269']

a, b, d, e, g, h, j, k, m, o, p, r, s, y