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: ['5761', '2289', '577', 't', '125', 'i', 'g', '9693', '747', 'd', '4829', '9587', 'f', 'k', 'w', 'v', '8607']

A: d, f, g, i, k, t, v, w
****
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']

A: a, b, c, f, g, h, j, k, p, r, v, w, x, y
****
Q: ['9243', '4867', 'z', '6945', 'g', 'k', 'l', '9673', '1341', 'i', 'n', 'd', '4903', '8751']

A:
d, g, i, k, l, n, z
****