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.

Ex Input:
['8887', '1199', 'r', '7209', 'k', '7567', '7239', 'k', '5123', 'w', '4523', 't', 'd', '5289', '5737', '485', 'w', 't', '7651', 'v', '7213', '7687', 'y', 'w', '7265', 'b', 'b', '3667', 'z', '9935', 'i', 'l', 'u', '6715', 'j', '9815', '8925', '7941', 'w', 'm', '3907', '621', '5523', '5849']

Ex Output:
b, d, i, j, k, l, m, r, t, u, v, w, y, z


Ex Input:
['2633', 'd', 'r', '8083', 'f', 'd', '5121', '8651', 'o', 'b', '811', '7551', 'x', 'p', 'm', 'v', 'm', '7833', '1959', 'y', 'p', '779', '1889']

Ex Output:
b, d, f, m, o, p, r, v, x, y


Ex Input:
['537', 'p', 'x', 'e', '3857', '9713', 'p', 'p', 's', 'h', '2703', 'f', 'u', '8859', '27', 'w', 'w', 'x', 'p', 'a', 'a', 'y', 'z', '2729', '8365', '8469', '9627', '8369', 'o', 'a', 'o', '2465', 'v', 'v', 's']

Ex Output:

a, e, f, h, o, p, s, u, v, w, x, y, z