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: ['7799', '8163', '3389', 'x', 'k', 'm', '6085', 'f', '1131']

A: f, k, m, x
****
Q: ['6175', '9441', '7127', '5979', 's', '1367', 'e', 'm', '7083', '1787', '8375', '2851', '3475', 'r', '697', 'g', 'z', 'm', '4207', 'c', '7971', 'z', '9339', 'd', 's', '3507', '9003', 'i', 'y', 'w', 'j', 'i']

A: c, d, e, g, i, j, m, r, s, w, y, z
****
Q: ['w', 'z', '3077', 'e', '8459', 'q', 'z', '3177', '8171', '7063']

A:
e, q, w, z
****