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: ['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: ['1979', 'b', 't', '1101', '7953', '2451', '7539', '6833', 'u', '49']

A: b, t, u
****
Q: ['151', '57', '4953', '5303', '5059', '8123', '1657', 'p', 'u', '2769', 'n', 'p', 'v', 'j', '1201', '4781', 'd', '6959', '2497', '3077', 'k', 'z', '7761', '1431', 'm', 'y', '4111', '9721', '4787', '3467', '2403', 'l', '391']

A:
d, j, k, l, m, n, p, u, v, y, z
****