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]: ['f', 'a', 'r', '4009', 'k', 'a', 'g', '7725', 'v', 'b', '6705', 'a', '6583', '3159', 'c', 'w', 'x', 'h', '7625', 'p', 'y', '5645', 'k', 'r', 'j', '4175', 'r', '3103', '8631', '5999', 'p', 'g', 'h']
[EX A]: a, b, c, f, g, h, j, k, p, r, v, w, x, y

[EX Q]: ['w', 'g', '1649', 'a', '2115', '6763', 'r', 't', 'l', 's', 'y', '5659', 'a', 'b']
[EX A]: a, b, g, l, r, s, t, w, y

[EX Q]: ['p', 's', '3053', 'a', 'n', '1283', 'l', '6549', 'u', 'u', '8735']
[EX A]:
a, l, n, p, s, u