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: ['1121', 'j', '1433', 'g', 'l', '1479', '1699', 'j', 'a', '8507', 'd', 'a', '5229', 'k', 'x', '4549', 'e', 'p', '1367', 'u', 'd', '785', '215', 'e', 'f', 'a', '101', '7575', '7965', 'p', 'i', '5637', '1005', 'i', 'y', '181', 'r']

Output: a, d, e, f, g, i, j, k, l, p, r, u, x, y


Input: Consider Input: ['315', '9975', '3013', 's', '6131', 'e', 'e', 'u', 'a', '1729', 'g', 't', 'y', 'f', '7523', 'e', 'g', '489', 'm', 'p', 'f', 'e', '2077', 'e', 'g', 'c', 'l', '6389', 'k', 'b']

Output: a, b, c, e, f, g, k, l, m, p, s, t, u, y


Input: Consider Input: ['a', '7053', '2595', '1629', 'g', 'a', '8965', 'd', '1983', 'j', '4473', '9103', '2937', 'o', '6297', '8885', '8361', '7677', '425', 'f', '847', '8709', '3985', 'r', '1047', '1471', 'w']


Output: a, d, f, g, j, o, r, w