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:
['g', '7517', '3173', 'd', '2143', 'n', '8507', 'l', '8369', '225', 'e', 'l', '9511', 'p', '1317', '5651', 'p', '1125', 't', '739', '6453', 'l', 'g', '8555', '8075', 'x', 's', 'd']

Ex Output:
d, e, g, l, n, p, s, t, x


Ex Input:
['7989', '6897', 'o', 'v', '5687', '2933', 'w', '8207', 'y', 's', 'w', '3013', 'h']

Ex Output:
h, o, s, v, w, y


Ex Input:
['u', '5809', 'p', 'q', '5563', '4921', 'd', '6121', '45', '539', '6549', '103', '4285', '6003', '5115', '7617', 'd', 'm', 's']

Ex Output:

d, m, p, q, s, u