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:
['v', 'l', 'v', '7673', '8975', 'u', '2471', '4151', '3615', '1139', 'i', 'z', '8833', 'v', '341', 'l', 'n', 'l', 'd', '9207', '1861', '3901', 'a']

Ex Output:
a, d, i, l, n, u, v, z


Ex Input:
['8381', 'j', '761', '5431', '7601', 'd', '4339', '1479', 'b', 'x', 'f', 'w', '2437', '7725', '6385', '411', 'w', 'w', 'i', '2769', '5709', '5703', 'k', '5301', '6503', '7833', 'y', '3813', '7061', '5531', 'n', '2251', 'y', '8941', '8481', 's', 't', 't', '3345', 'k', '1545']

Ex Output:
b, d, f, i, j, k, n, s, t, w, x, y


Ex Input:
['t', 'q', '8385', 'k', 'p', '8481', 'w', 'w', '7939', '5843', '9395', 'c', 'r', 'l', 'g', 'v']

Ex Output:

c, g, k, l, p, q, r, t, v, w