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]: ['277', '8697', 'q', '2023', '5723', 'm', '8673', 'f', 'z', 'z', 'a', '9875', 'p', 'x', 'l', 'z', 'x', '619', '6509', 's', '2067', '571', 't']
[A]: a, f, l, m, p, q, s, t, x, z


[Q]: ['3995', 'n', 'z', '8389', '7857', '3005', 'i', 'e', '1117', 'z', '8251', 'r', 't']
[A]: e, i, n, r, t, z


[Q]: ['z', '4545', '8601', 'p', '1117', 'g', '6475', 'g', 'o', 'a', 'k', '6219', 'j', 'i', '5033', '9637', '4095', 'y', 'j', 'n', '2593', 'n', 'e', 'n', 'h', '8447', '6487', '1419', 'a']
[A]:
a, e, g, h, i, j, k, n, o, p, y, z