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:
['8495', 'p', 'j', 'm', 'n', '9115', '1183', 'r', 'r', '8735', 'a', 'i', 'k', 'p', '8927', 'r', '9283', '9563', 'g', '2503', 'h', '1091', '5257', 'a', '3061', '2835', 'l', 'w', 'j', '7617', '8793', '7463', 'h', '8467', '7337', 'b', '4655', 'd']

Ex Output:
a, b, d, g, h, i, j, k, l, m, n, p, r, w


Ex Input:
['4269', '1847', '2025', '601', 'g', 'n', 'h', '3499', '4977', '3579', '9355', '3489', 'm', 'm', '4401', '4605', 'l', '3977', 'h', 'd', 't', '5135', '7787', 'k', 'q', '7699', '5325', '6269', '1865', 'h', '8915', '5677', 'g', '603', '1435']

Ex Output:
d, g, h, k, l, m, n, q, t


Ex Input:
['9703', '1875', '3767', '7537', '4509', '5645', 'z', 'l', '3747', '1897', '3849', '6973', 'e', 'm', 'k', 'k', '4053', 'g', 't', '4341', '6811', 'e', '1979', '8413', 'i', '2315', 'a', 'w', 'p', '1939', '4879', '1337', 'x', 'u']

Ex Output:

a, e, g, i, k, l, m, p, t, u, w, x, z