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:
['2505', '4199', 'e', '5433', '8795', 'q', 'i', '9357', 'o', '257', '8235', 'b', '1339', 'w', '1463', 'm', '277', '3211', '3863', 'r', 'm', 'i', '5793', '7451', '4787', '4739', 'k', 't', 'o', '7453', '9385', 'v', 'l', 'y', 'f', 'r', 'p', 'w']

Ex Output:
b, e, f, i, k, l, m, o, p, q, r, t, v, w, y


Ex Input:
['n', 'w', '6735', '3427', '6115', 'q', '7851', '3645', 'g', '6825', '6515', '4885', 'z']

Ex Output:
g, n, q, w, z


Ex Input:
['f', '5081', '2015', '6171', '3329', 'l', '6603', '7489', 'i', 'n', 'v']

Ex Output:

f, i, l, n, v