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]: ['9689', '9727', 't', 'd', '2103', 'c', 'n', '8553', '4559', '7815', 'u', 'l', 'c', 'e', 'u', 'n', '7207', '4875', '7699', 'h']
[A]: c, d, e, h, l, n, t, u


[Q]: ['7073', 'd', 'e']
[A]: d, e


[Q]: ['1213', 'y', 'v', '7663', 'e', 'i', 'e', '7545', 'o', 'l', '1089', 'z', 'p', 's', 'j', 't', 'g', 'm', 'k', '9705', 'u', '2029', '97', 's', 'k', 'c', 'j', 'a', 'k', 'r', 'r', 'z', '4961', 't', 'r', 'q']
[A]:
a, c, e, g, i, j, k, l, m, o, p, q, r, s, t, u, v, y, z