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:
['a', 'y', '7401', 'e', 'l', '4351', 'p', '5673', 'k', '333', 'o', 'd', 'e', 'j', 'e', '9569', '1795', 'r', 'z', '6059', '4399', '2927', 'n', '9387', '9317', 'b', 'c', 'e']

Ex Output:
a, b, c, d, e, j, k, l, n, o, p, r, y, z


Ex Input:
['7055', '2573', '1713', 'x', 'm']

Ex Output:
m, x


Ex Input:
['727', '7807', '4369', '421', '7725', 'f', 'k', 'z', '9975', 'c', 'e', '201', '975', 'j', '5097', 'j', '8925', 'x', 'c', 'f', '4119', '7191']

Ex Output:

c, e, f, j, k, x, z