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]: ['s', 'w', '8949', '4025']
[A]: s, w


[Q]: ['x', 'j', '9747', 'i', '2015', '3505', 'q', 'n', 'h', '3011', 'u', '8043', 'j', 'f', 'd', 'a', 'p', '5817', 'l', 'q', '2275', 'n', '7085', '5373', 'l', 'g', 'b', '8043', '3085']
[A]: a, b, d, f, g, h, i, j, l, n, p, q, u, x


[Q]: ['t', 'h', '3851', 'e', 's', 'x', 'r', '879', 'o', 'u']
[A]:
e, h, o, r, s, t, u, x