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]: ['d', '771', '4193', 'e', '1537', 'a', 'q']
[A]: a, d, e, q


[Q]: ['o', 'h', 'z', 'n', 'e', 'y', 't', '4371', 'm', '1059', '4853', '8529', 'l']
[A]: e, h, l, m, n, o, t, y, z


[Q]: ['4551', 'x', 'f', '4851', '9597', 'h', 'y', '6905', 'g', 'k', 'u', 'l', '3881', 'z', '4453', '7567', '4429', '6423', 'f', '705', 'k', 'c', 'k', 'z', 'c', '1597', 'o', '2555', '1409', 'z', '1325', 'y', 'y', '6285', '5895', '4581', 'u', '5007', '2559', '3575', '3541', 'q', '8703', 'h']
[A]:
c, f, g, h, k, l, o, q, u, x, y, z