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: Consider Input: ['1367', 'h', '4153', '1587', 'h', 'b', 'n', 'u', 'n']

Output: b, h, n, u


Input: Consider Input: ['8975', '7199']

Output: -1


Input: Consider Input: ['f', 'u', '9025', 'i', 'n', '1125', 'i', '2289', 'g', '6057', 'k', 'r', '8341', 's', 't', '3637', 'j', '4785', '8595']


Output: f, g, i, j, k, n, r, s, t, u