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]: ['7367', '9757', '9431', 'h', 'a', 'k', '5833', '6237', 'g', '3585', '8665', 'g', '7517', '1561', 'p', 'p', '1307', '3325', 'q']
[A]: a, g, h, k, p, q


[Q]: ['491', '229', 'g', '6677', '4793', 'h', 'x', 'a', '2333', 'u', 'l', '785', 'p', '7331', '653', '5193', '5415', '8417', 'v']
[A]: a, g, h, l, p, u, v, x


[Q]: ['y', '5625', 'y', '9751', 'r', 'o', '21', '4429', 'y', '3541', '899', 'f', 'e', '5369']
[A]:
e, f, o, r, y