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.

[EX Q]: ['895', '2049', '8839', '1773', 'v', '467']
[EX A]: v

[EX 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']
[EX A]: a, b, d, f, g, h, i, j, l, n, p, q, u, x

[EX Q]: ['d', 'b', '4039', '3549', 's', '2239', '3515', '5119', '8731', 'q', '2901', '565', '7101', 'a', 'c', 'm', 'j', '6941']
[EX A]:
a, b, c, d, j, m, q, s