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:
['y', '8115', 'f', '5333', 'f', '3437', 'b', 'e', '5719', 'm', 'w', '95', '4863', 'k', '4895', 'a', '8179', 'm', '7919', '1731', '229', 'r', '1847', '7559', '6669']

Ex Output:
a, b, e, f, k, m, r, w, y


Ex Input:
['3995', 'n', 'z', '8389', '7857', '3005', 'i', 'e', '1117', 'z', '8251', 'r', 't']

Ex Output:
e, i, n, r, t, z


Ex Input:
['9355', '8175', '3255', 'n', '3421', 'c', '2585', '1881', 'v', 'j', '4947', 'u', 'q', '375', 'b', 'a', '2425']

Ex Output:

a, b, c, j, n, q, u, v