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.

[Q]: ['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']
[A]: a, f, h, i, j, k, l, n, p, q, r, u, v, w, x, y


[Q]: ['j', 'r', 'z', 'f', '1485', '2419', 't', 'd', '6023']
[A]: d, f, j, r, t, z


[Q]: ['4107', 'g', 'l', '2875', 'r', 'c', 'b', 'a', '239', '3945', 'm', '5733', '8571', '8619', 'n', 'x', 'h', '4165', '6599', 'y', 'x', 'x', 'u', 'i', 'y']
[A]:
a, b, c, g, h, i, l, m, n, r, u, x, y


