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.

[EX Q]: ['6463', '871', '5781', '283', '9653', 'f', '9661', '3365', '2889', '5499']
[EX A]: f

[EX Q]: ['s', '2507', '3091', 'g', '7643', '2573', 'w', 'r', '1977', 'q', 'c', 'j', '1335', '9671', '7317', '567', '2041', '5777', 'w', 'm']
[EX A]: c, g, j, m, q, r, s, w

[EX Q]: ['n', 'y', '7087', '9539', 'x', 'i', 'w', '7237', '8613', 'k', '5999', '4179', 'o', 'm', '7485', '1955', 'w', '1451', 'h']
[EX A]:
h, i, k, m, n, o, w, x, y