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]: ['w', '9437', 's', '9819', 'q', 'q', '4443', 'p', '377', '6777', 's', 'x', 'a', 'o', '9205', '9289', '7103', 'k', 'l', '9453', '9043', 'k', 'r', 'g']
[EX A]: a, g, k, l, o, p, q, r, s, w, x

[EX Q]: ['n', 't', '2901', '9697', 'a', 'j', 'x', 'a', '4437', '2255', '2177', 's', '3173', 'j', 't', '5713', '4091', '4253', '5553', 'i', '4533', 'i', 'e', '6899', 's', '3541', '2139', '2705', 'm', 'u']
[EX A]: a, e, i, j, m, n, s, t, u, x

[EX Q]: ['a', '6783', 'o', 't', '2933', 'l', '1335', 'z', 'i', '6147', 'v', '3415', '9963', '1281', 'z', 'y', 'c']
[EX A]:
a, c, i, l, o, t, v, y, z