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:
['6597', '7889', 'x', 'v', 'm', 'j', 'j', 'w', 'v', '177', 'x', '8353', '5897']

Ex Output:
j, m, v, w, x


Ex Input:
['6411', 'x', 'i', '267', 'z', 'e', '5483', '8033', '3697', 'z', '4167', 'e', 'f', '7229', 'i', 't', '2197', 'g']

Ex Output:
e, f, g, i, t, x, z


Ex Input:
['5539', 'c', '8343', '8777', '4977', '3595', '8677', '7697', 'd', 'k', '8917', '4565', 'y', '8537', '8547', 's', 'i', 'y', 'p', '1827', 'c', 'l', 'z', '6159', '7379', 'r', '9653', '3965', 'i', 'h', '7695', 'i', '5035', 'm', '1315', '4191', 'e']

Ex Output:

c, d, e, h, i, k, l, m, p, r, s, y, z


