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:
['q', '6421', 'w', 'x', '669', 'h', '3853', '6609', 'p', '947', 'g', 'c', 'x', '2617', 'v', 'e', '4795', '5755', 'a', '2379', 'y', '5939', 'l', 'h', 'g', '3779', 'c', 'm', '3157', '4027', 'g', '2917', '9461', '7271', 't', 'i', '9807', '147']

Ex Output:
a, c, e, g, h, i, l, m, p, q, t, v, w, x, y


Ex Input:
['c', '8785', 'u', 'i', 'i', '6513', '6093', 'w', 'i', 'x', '9377', 'p', '1545', '7997', 'a', 'c', '125', 'u', '9149', '9103', 'u', 'o', 'h', '2275', '8503', '3251', 'c', '9925', 'w', '6873', 'c', 'h', 'e', '2369', 'c', 'z', '1337', '9541', '675', 's']

Ex Output:
a, c, e, h, i, o, p, s, u, w, x, z


Ex Input:
['5055', '5481', 'd', '1321', '6245', '3577', '91', '1375', 'y', '8143', 'u', '9755', '6275', '8631', '2061', '8963', 'p', 'w', '4791', '1911', 'o', '4857', '6949', '1721', 'i', 'r', 'h', 'n', 'd', 'n', '5621', '4969', '6945', 'd', 'i', 'm', '6151', 'x']

Ex Output:

d, h, i, m, n, o, p, r, u, w, x, y