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:
['j', '1733', 'p', '6741', '7933', '8943', '733', 'x', '1107', 'z', '1719', '7653', 'y', 'z', '6563', 'p', '4615', 'j', '4489', 'h', 'w', 'y', 'p', 'c', '7949', 'k', 'm', 'r', '9427', '7243', '9777', 'j', '323', '4095', 't']

Ex Output:
c, h, j, k, m, p, r, t, w, x, y, z


Ex Input:
['n', '9571', '2983', '7597', 'v', 'y', '1993', '1403', '8309', '7043', 'c', '7329', 'p', '4479', 'p']

Ex Output:
c, n, p, v, y


Ex Input:
['7171', 'o', 'l', '55', '257', 'a', 'z', '9115', '1105', '4705', '6885', 'd', '8061', '3341', 'h', 'y', '2139', 'k', '2411', '785', '5405', 'b', '2205', '3177', 'u', '6057', '935']

Ex Output:

a, b, d, h, k, l, o, u, y, z