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]: ['2819', 'k', 'u', 'a', '4575', 'a', 't', 'a', 'f', '1507', '415', 'w', 'o', 'o']
[A]: a, f, k, o, t, u, w


[Q]: ['k', '8917', '3773', '6723', 'r', 'z', '3265', 'o', 'f', 'q', '9343', 'f', '1925', 'u', 'b', 'o', '5275', 'b', 'n', 'd', 'j', '4825']
[A]: b, d, f, j, k, n, o, q, r, u, z


[Q]: ['z', '4731', '3317', 't', 'w', '3191', '8381', 'x', 'u', 'n', 'c', 'r', 'j', 'y', '5923', 'r', '4323', '3815', 'p', '3903', '2593', '4329', 'h', '903', 'r', '265', 'i', '1813', '3901', 'k']
[A]:
c, h, i, j, k, n, p, r, t, u, w, x, y, z