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: ['3395', '7471', 'n', '9537', '1255', '1997', '3085', '4863', '9797', '4275', 'k', 'f', '8973', '3939', 'p', 'q', '4977', '6231', '8745']

A: f, k, n, p, q
****
Q: ['d', '6003', 'k', '1987', '1877', 'a', '2615', 'n', 's', 'f', 'b', 'm', '1149', '8293', '5803', 'e', '2697', '5917', 'p', '6035', '2385', 'i', 'u', 'm', '9565', '4523', 'b', 'v', '2577', '9725', '6093', '6203', '4197', '8477', 'o', 'd', '3637', '9827', '5523', '7189', 'j', '8893', 'h', 'q']

A: a, b, d, e, f, h, i, j, k, m, n, o, p, q, s, u, v
****
Q: ['8359', 'k', 'e', '1613', '127', 'r', '9347', 'x', '8489', 'q', 'w', '9435', 'k', 'a', 'k', 'b', '5539', '8941', 'k', '2331', 'c', 'h', '7257', '6949', '9857', '9711', 'h', '1323', '4051', '7879', 'l', 'r', '6729', '1165', 'b', 'r', 'u', 'w', 'q']

A:
a, b, c, e, h, k, l, q, r, u, w, x
****