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 Q]: ['1121', 'j', '1433', 'g', 'l', '1479', '1699', 'j', 'a', '8507', 'd', 'a', '5229', 'k', 'x', '4549', 'e', 'p', '1367', 'u', 'd', '785', '215', 'e', 'f', 'a', '101', '7575', '7965', 'p', 'i', '5637', '1005', 'i', 'y', '181', 'r']
[EX A]: a, d, e, f, g, i, j, k, l, p, r, u, x, y

[EX Q]: ['6249', '1235']
[EX A]: -1

[EX Q]: ['5163', '1413', 'x', '4915', 'y', '6895', 'd', 'q', '3889', 'g', '7327', 'b', 'l', '9647', 'f', '2197', 'h', '9183', '861', 'f', 'z']
[EX A]:
b, d, f, g, h, l, q, x, y, z