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: ['i', 'x', 'n', 'w', '8915', 'd', 'd', 'd', '6025', '7861']

A: d, i, n, w, x
****
Q: ['1931', 'c', 's', '8767', 'z', '8977', '9249', '365', 'p', '7187', 'p', '961', 'k', 'k', '423', '5999', '4697', '6251', '6441', '1821', 's', 's', 'f', '5365', 'z', '5113', 'y', 'k', 'i', '5627', 'u', 'w', '4103', '8035', '7105', 'o', 'n', 's', 'y']

A: c, f, i, k, n, o, p, s, u, w, y, z
****
Q: ['o', '5099', 'k', 'w', '3109', 'o', 'i', '5771', 'm', 'g', '6229', 'w', '8423', '6369', '2263', 'y', 'j', '4339', 't', '1393']

A:
g, i, j, k, m, o, t, w, y
****