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: ['f', 'a', 'r', '4009', 'k', 'a', 'g', '7725', 'v', 'b', '6705', 'a', '6583', '3159', 'c', 'w', 'x', 'h', '7625', 'p', 'y', '5645', 'k', 'r', 'j', '4175', 'r', '3103', '8631', '5999', 'p', 'g', 'h']

A: a, b, c, f, g, h, j, k, p, r, v, w, x, y
****
Q: ['3127', '9253', '5667', '9453']

A: -1
****
Q: ['s', '7143', 'u', '2021', '9889', 'q', 'g', '6223', '5039', '2447', '8663', 'u', 'o', 'p', '6293', '3291', 'p', '3907', 'p', '5195', '4823', '591', '9559', '4019', '265', '4797', 't', 'q', '9629', '9471', '3851', 'l']

A:
g, l, o, p, q, s, t, u
****
