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]: ['6643', '6757', 'h', '1033', 's', 'c', '2003', 'p', '5483', 'f']
[EX A]: c, f, h, p, s

[EX Q]: ['9403', '9881', '8391', 't', '1793', 'w', 'x', 'y', '6383', 'j', 'r', '5323', 'r', 'l', 'e', 'u', '7193', '2309', '837', 'z', 'w', 'n', '4427', '8269', '6333', 'a', 'p', '1933', '8497', '2665', '1349', '6807', '9009', 'b']
[EX A]: a, b, e, j, l, n, p, r, t, u, w, x, y, z

[EX Q]: ['f', '3409', 'i', '4147', '1745', '6007', 'l', 'd', 'i']
[EX A]:
d, f, i, l