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]: ['6597', '7889', 'x', 'v', 'm', 'j', 'j', 'w', 'v', '177', 'x', '8353', '5897']
[A]: j, m, v, w, x


[Q]: ['7155', 'y', '145', '7147', 'u', '8453', 'd', '3693', '6471', '5289', 'n', 'p', '8289', '2929', '199', 'e', '8377', '8937', '5315', 't', 'l', '7715', 'c', 'y', 'f', '9999', 'p', '3655', '5489', 'q', '2321', '9881', '2265', 'n', 'v', '455']
[A]: c, d, e, f, l, n, p, q, t, u, v, y


[Q]: ['z', 'z', 'x', 'f', 'i', 'a', '4429', '241', '9693', 'e', 'l', '4859', '2015', 'a', 'b', '723', '8369', '7829', 'n', 'u', 'f', 'o', '9437', '3765', 'c', 'u']
[A]:
a, b, c, e, f, i, l, n, o, u, x, z