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:
['k', 'c', 'i']

Ex Output:
c, i, k


Ex Input:
['3307', 'r', '2665', '3453', 'f', 'd', 'v', '3801', '3153', '3137', 'y', 'i', '9681', 'k', '9253', 'y', 'i', '8631', '2375', '5131', 'r', 'z', '8645', '595', 's', '6749', '2665', '709', '8203']

Ex Output:
d, f, i, k, r, s, v, y, z


Ex Input:
['9033', '2621', 'w', 'w', 'o', '1631', 't', 'q', 'z', '6857', 'k', 'p', 'c', 't', '2389', '3801', '961', '4347', '6277', '9161', 'c', '261', 'a', '2085', '3747', 'p', '1015', 'y', 'l', '1261', 'b', 'k', '851', 'g', 't', '441', 'l']

Ex Output:

a, b, c, g, k, l, o, p, q, t, w, y, z