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.

Q: ['n', 'q', '6461', 's', '8565', '2237', '2071', '8143', '2977', '5511', 'j', 'o', '5793', 'j', 'm', 'n', '8031', 'j', '535', '5001', 's', 'y', '1737']

A: j, m, n, o, q, s, y
****
Q: ['5163', 'n', 'j', '67', '3801', 'n', '7113', 'z', '579', '6885', '8921', 'v', '5481', '5507', 'k', '8403', 'c', '837', 'u', '6341', 'd', 'i', '497']

A: c, d, i, j, k, n, u, v, z
****
Q: ['6045', 'd', 'z', 'y', '1643', '3807', 's', '8079', 'k', '8837', 'g', '5263', 'y', '1749', '6377', 'n', 'u', 'l', '9025', 'n', 't', '1153', 'd', 'u', '4289', 'w', 'r', '233', 'v', '1295', 's', '6961', 't']

A:
d, g, k, l, n, r, s, t, u, v, w, y, z
****