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:
['1649', 'l', 'i', '5901', 'o', 'g', '1197', 'a', '9327', '9835', '1095', 'k', '4489', '9149', 'o', '3095', 'z', 'u', 'y', '561', '7419', 't', 'j', '8763', 'v', '339', 'y', 'w', 'v', 'v', '1867', 'd', 'r', 'w', 'h', 'j', '1531', '3841']

Ex Output:
a, d, g, h, i, j, k, l, o, r, t, u, v, w, y, z


Ex Input:
['1971', 'g', 't', 't', 'x', 'q', 'o', 'm', 'h', '9481', '1729', '5527', 'u', '3157', 's', '8795', 'z', 'g', 'i', '1649', 'p', '65', 's', 'u', '6843', 'r', 'l', 'k', 'n', 's', 'm', '7991', 'u', 'a']

Ex Output:
a, g, h, i, k, l, m, n, o, p, q, r, s, t, u, x, z


Ex Input:
['w', 'w', 'z', '2287', 'u', 'p']

Ex Output:

p, u, w, z