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:
['r', 'q', '3649', 't', '3941', 'z', '3729', 's', 'g', '6905', 'h', 'v', '1085', '6353', 'a', '9395', '5433', 'a', '2565', 'p', 'a', 'h', '1491', 'j', 'b', 'v', 'e']

Ex Output:
a, b, e, g, h, j, p, q, r, s, t, v, z


Ex Input:
['d', '771', '4193', 'e', '1537', 'a', 'q']

Ex Output:
a, d, e, q


Ex Input:
['1235', '9341', '8447', 'k', '9743', '9147', '8899', 'n', '2187', 'o', 'q', 'o', '9905', 'v', '9131', 'u', '8301', 'x', 'i', 'e', 'z', 'v', 'r', '4385', 's']

Ex Output:

e, i, k, n, o, q, r, s, u, v, x, z