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]: ['e', 'z', '5199', 'x']
[A]: e, x, z


[Q]: ['l', 'g', 'd', 'p', '8163', '6643', 'o', 'p', 'm']
[A]: d, g, l, m, o, p


[Q]: ['z', 'o', 'y', 'p', 't', '8441', '5965', '123', 'v', 'u', '1425', 't', 'a', 't', 'i', 'u', 'l', 'j', '5943', 'h', '1269', 'b', 'f', '8303', '7575', 'q']
[A]:
a, b, f, h, i, j, l, o, p, q, t, u, v, y, z