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:
['p', 'p', '7899', 'u', '971', '7289', 't', '5217', 'k', 'z', 'y', 'y', '6905', '9499', '4085', 'x', '955', 'v', 'j', '9049', '7927', '1757', '193', '2181']

Ex Output:
j, k, p, t, u, v, x, y, 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:
['8913', '8925', '4877', '1049', 'v', 'w', 'z', 'n', '8919', 'w', 'r', 'o', 'l', '8761', '7873', 'p', 'y', 'h', '4389', '1691', '8221']

Ex Output:

h, l, n, o, p, r, v, w, y, z