instruction:
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.
question:
['7065', 'f', 'k', 'i', 'd', '8291', 'z', 'e', 'q', '5345', 'h', '3397', 's', '5355', 's', '9033', 'e', '5241', '5285', 'm', 'h', 'i', 'n', '6471', '3365', 'f', 'r', '6145', 't', '4869']
answer:
d, e, f, h, i, k, m, n, q, r, s, t, z


question:
['j', '8797', 'i', '5443', 'i', 'f', '7593', 'u', 'h', '3251', 'l', '681', 'y', 'n', 'r', '1699', '1379', '8987', '6955', 'x', 'p', 'x', '553', 'q', '5679', 'q', 'w', '9007', 'r', '8945', '7351', 'a', 'v', 'k', '1309', 'v', 'i', '4161', 'a', 'q', '2919', '6917', '6845']
answer:
a, f, h, i, j, k, l, n, p, q, r, u, v, w, x, y


question:
['5253', '4551', '955', 't', 'h', '2845', 'c', '1691', '1431', 'u', '7435', 't', 's', '2641', 'x', '6421', 'l', 'f', '2241', '6911', 'm', '2093', '6983']
answer:

c, f, h, l, m, s, t, u, x