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:
['8311', 'w', 'f', '3431', '9863', '5817', '3969', '2705', 'x', 'm', 'k', 'z', 'z', '235', 'x', '417', 's', 'i', 'y', '8833', '8675', 's', 'm', '2149', '765', 'u', '1021', '7823', 'x', '7275', '3157', 'k']

Ex Output:
f, i, k, m, s, u, w, x, y, z


Ex Input:
['9467', 'o', '8347', '7125', '7999', '1737', 'h', '7043', '8617', '2033', '9959', '2349', 'p', '9389', '5525', 'w', 'u', 'p', '4703', '9807', 's', 'f', '2359', '7357', '2471', '5447', 'f', 'w', '2865', '6627', '3211', 'y', '23', 'z', 's', '1517', '3553', 'r', '2251']

Ex Output:
f, h, o, p, r, s, u, w, y, z


Ex Input:
['7057', '3325', 'r', 'r', '4871', '1683', 'i', '8431', '8381', 'r', 'l', 'm', 'z', 'p', 'k', '9597', 'g', 'c', '1281', '2727', '663', 'h', 'k', '2749', '3079', '5803', 'h', '8883', 'd', 'l', '4273', '5321']

Ex Output:

c, d, g, h, i, k, l, m, p, r, z