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]: ['5193', 'h', 'm', '703']
[A]: h, m


[Q]: ['w', 'o', 'l', '1857', 's', 'q', 'j', 'e', '5945', 'g', 'l', '9563', 'e', 'u', '7633', '7977', '4943', 'y', '5621', 'f', '1653', 'c', 'l', '2843', '2125', '7731', '5257', '5667', 'b', 'b', '5765', 'a', 't', '8163', '9785', '5385']
[A]: a, b, c, e, f, g, j, l, o, q, s, t, u, w, y


[Q]: ['7503', '9861', 'p', 'v', '7621', 'n', '5699', 'i', 'j', '2413', 'b', '5239', '1645', '2447', 'x', 'b', 'w']
[A]:
b, i, j, n, p, v, w, x