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:
['7367', '9757', '9431', 'h', 'a', 'k', '5833', '6237', 'g', '3585', '8665', 'g', '7517', '1561', 'p', 'p', '1307', '3325', 'q']

Ex Output:
a, g, h, k, p, q


Ex Input:
['x', 'i', 'k', 'c', 'f', '3057', '481', '5887', '847', 'c', 'x', 't', 'g', '5805', 'a', 'i', '2885', '403', 'x', 'c', '4815', '2765', 'c', '5181', 'l', 'e', '3843', '1171', 'u', '7867', 'z', 'e', '9349', '5011', 'h', 'x', '3193', 'i', '4595', '8621', '6007', '1879']

Ex Output:
a, c, e, f, g, h, i, k, l, t, u, x, z


Ex Input:
['s', 'u', 'w', '7289', 'u', 'i', '7819', '1791', '161', '8555', '1003', 'e', 'a', 'a', 'f', 'j', '2097', 'h', '9541', 'a', '3101', 'j', 'b', '3389', 'e', '6057', 'x', '9375', '9305', 'f', 'b', '1825', '5905', 'l', 'v', 'j', 'o', '2871', '8743', 'a', '8485', 'p', 'h', 'x', '2223']

Ex Output:

a, b, e, f, h, i, j, l, o, p, s, u, v, w, x