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:
['5161', 'v', 'y', '6005', 'y', 'l', '5451', 'z', 'j', 'd', '4597', '9319', '1241', 'g', 'f', 'b', 'g', '683', '763', 'm']

Ex Output:
b, d, f, g, j, l, m, v, 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:
['1865', 'm', 'l', '343', 'w', 'y', '7235', '1037', '7977', '7811', 'f', 'n', 'c', '8711', '7481', '4959', '6293', 'z', '863', '7711', 'q', 'l', 's', 'z', '5021', 's', 'h']

Ex Output:

c, f, h, l, m, n, q, s, w, y, z