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:
['f', 'p', 'n', '839', '9229', 'r', '7661', 'c', '4383', 'u', 'k', '5321', '3181', '1785', 'w', 'k', '8721', '7855', '4093', '6495', 'q', '2467', 'g']

Ex Output:
c, f, g, k, n, p, q, r, u, w


Ex Input:
['g', '6867', '7965', '3313', 'k', '1827', '7337', 'u', '1209', '5145', 'w', 'h', '9059', 'u', 'b', '3189', '2837', 'k', 'y', 'e', 'b', '4479', '541', '7103', 'h', 'm', '2177', '6377', '3993', '7167', 'q', '2145', '5007', '9135', '5331', 'e']

Ex Output:
b, e, g, h, k, m, q, u, w, y


Ex Input:
['3003', 'w', 'l', '8979', 'v', 'd', '3375', '6959', 'z', '9009', 'y', 'c', 's', '3189', '1403', '1367', 'j', '9197', '4251', '2247', '2049', '4111', 'a', '4363', '7863', 'u', '309', 'q', 'w', 'm', 'l', 'o', 'n', 'x', 'a', 'v', '3605', '4243', 'v', 'w', '9443', '9675', '1009', '1287']

Ex Output:

a, c, d, j, l, m, n, o, q, s, u, v, w, x, y, z