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: ['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']

A: b, d, f, i, j, k, n, s, t, w, x, y
****
Q: ['7367', '9757', '9431', 'h', 'a', 'k', '5833', '6237', 'g', '3585', '8665', 'g', '7517', '1561', 'p', 'p', '1307', '3325', 'q']

A: a, g, h, k, p, q
****
Q: ['w', '491', 'x', 'u', 'z', 'q', '5411', '7629', '8261', '8629', '1441', '5139', 's', 'm', '6463', 'u', 'z']

A:
m, q, s, u, w, x, z
****