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:
['1121', 'j', '1433', 'g', 'l', '1479', '1699', 'j', 'a', '8507', 'd', 'a', '5229', 'k', 'x', '4549', 'e', 'p', '1367', 'u', 'd', '785', '215', 'e', 'f', 'a', '101', '7575', '7965', 'p', 'i', '5637', '1005', 'i', 'y', '181', 'r']

Ex Output:
a, d, e, f, g, i, j, k, l, p, r, u, x, y


Ex Input:
['w', '743', '5757', '8731', 'k', 'p', '317', 'n', 'x', '5649', 'l', 'm', 'c', '2499', 'l']

Ex Output:
c, k, l, m, n, p, w, x


Ex Input:
['p', '997', '1805', '9039', '4647', '6499', '8697', '6769', '5453', 'p', '4127', '4031', '6195', 'z', '877', 'e', 'q', '5233', 'v', 'l', 'f', 'q', 'z', 'i', '4459', 'e', '4607', '933', 'l', 'r', '2583', '8867', 'p', 'e', 'g', 'y', '7895', '6329', '3571', '949', 'l']

Ex Output:

e, f, g, i, l, p, q, r, v, y, z