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: ['q', 'g', 's', 'g', 'z', '987', '777']

Output: g, q, s, z


Input: Consider Input: ['6411', 'x', 'i', '267', 'z', 'e', '5483', '8033', '3697', 'z', '4167', 'e', 'f', '7229', 'i', 't', '2197', 'g']

Output: e, f, g, i, t, x, z


Input: Consider Input: ['7129', 'v', 's', '5371', '1789', 't', 'i', '8287', '3931', '8905', '1363', 'e', 'r', 'l', '533', '7949', '7591', 'n', '4679', '8453', 'd', '4385', '2379', '6627', '5951', '4505', 'd', 'j', '473', '9391', 's', '4661', 'e', '4527', '4095', 'b', '871', 'y', 'a', 'k', 'h', '4307', '5977']


Output: a, b, d, e, h, i, j, k, l, n, r, s, t, v, y