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:
['2047', '4403', 'g', '3017', '1627', 'v', 'r', '2237', '5513', 'o', 'v', '7229', '9801', 'j', '443', 'z', 'q', 'y', '7447', '1659', '3411', '55', '5153', '9921', '2195', '1075', '8187', 'p', 'x', 'h', 'y', 't', 'a', 'r', 'f']

Ex Output:
a, f, g, h, j, o, p, q, r, t, v, x, y, z


Ex Input:
['d', 'o', '7643', '9065']

Ex Output:
d, o


Ex Input:
['6643', '1839', 'a', '8725', '8519', 'a', 'x', '2959', '9843', '6657', 'z', 'j', 'n', 'r', '3441', '3329']

Ex Output:

a, j, n, r, x, z