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: ['g', 'u', 'q', '1375', '9491', 't', 'w', 'c', 'v', 'y', '3169', '1607']

A: c, g, q, t, u, v, w, y
****
Q: ['v', '6635', '5395', '3263', '4391', 'h', '1521', 'f', '9861', '6125', '1673', '3679', '8681', '4967', 'f', 'a', 'c', 'k', 'n', '4155', 'e', 'm', 'i', '1699', 'r', 'f', 'u', 'r', '3451', 'v', '7239', 'o', '4359', 'l', 'a', '2925']

A: a, c, e, f, h, i, k, l, m, n, o, r, u, v
****
Q: ['8859', '575', 'l', 'e', '6575', '1303', '8643', '1395', '3171']

A:
e, l
****