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: ['g', '4165', 'n', 'w', 'n', 'e']

A: e, g, n, w
****
Q: ['s', 's', '6581', 'e', '7355', '1315']

A: e, s
****
Q: ['u', '4013', '6239', '8767', 'g', '4623', 'v', '8437', '4023', '2139', '7315', '4427', '9143', 'z', '7905', '9661', 'a', 'p', 'y', 's', '7093', '4131', 'a', '1211', 'd', 'l', 'i', 'e', '5491', '2589', '6005']

A:
a, d, e, g, i, l, p, s, u, v, y, z
****