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 Input:
['f', '165', 'm', '9975', '9259', '6505', 'a', 'g', 's', '1127', 'h', 'n', 'c', '6475', 'c', '8657', 'a', '4057', 'm', 'y', 'w', 'm', '6567', '7297', '285']

Ex Output:
a, c, f, g, h, m, n, s, w, y


Ex Input:
['n', '7337', '6887', '2203', '4663', '2837', '6451', '959', '8027', 'p', 'v', 'q', 'g', '8059', '6151', 'v', '7097', '6583', '7637', '2367', 'w', '9603', '5365', '3773', '1707', 'k', 'x', 's', 'c', 'u', '3641', '6137', '1207', 'k', '5531', '4543']

Ex Output:
c, g, k, n, p, q, s, u, v, w, x


Ex Input:
['w', 'j', '8015', 'u', 'y', 'u', 'y', 'c', 'y', '3771', '3163', 'i', 'j', '2977', 'v', 'd', 'b', '3409', '4251', 'd', '5331', '1667', '671', '3057', '5217', '9193', 'h', 'i', '7819', 'e']

Ex Output:

b, c, d, e, h, i, j, u, v, w, y