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:
['5499', 'm', '327', 'h', '5765', '4231', 'y', 'g', 's', '883', '9843', '2751', '8967', 'z', '2301', 'l', 'l', 'k', '7843', '7221', '3643', 'k', '5951', 'r', '9441', '235', '3835', 'l', 'e', 'y', '4061', 'l', '1177']

Ex Output:
e, g, h, k, l, m, r, s, y, z


Ex Input:
['j', 'r', 'z', 'f', '1485', '2419', 't', 'd', '6023']

Ex Output:
d, f, j, r, t, z


Ex Input:
['3783', '5363', '7827', 'j', 'j', 'z', 'g', '6787', '9555', 'a', 'v', 'y', 'c', 'y', '6971']

Ex Output:

a, c, g, j, v, y, z