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]: ['v', '2989', 'z', '7843', 'e', '9923', 'y', 'b', '7611', 'u', 'u', '6227', '3145', 'w', '6451', 'g', '3129', 'o', 'r', 'z', '8349', 'u', 'h', 'd', 'g', 'a']
[A]: a, b, d, e, g, h, o, r, u, v, w, y, z


[Q]: ['o', 'z', 'h', '3965', 'n', '3009', '173', '997', '3987', '5799', '2331', 'p', 'x', '897', '8213', '451', 'u', 't', 't', '9917', '4501', 't', 'c', 'i', 'w', 'w', 'u', '2977', 't', 'b', '4161', '9281', 'w', 'f', '3137', '5745', 'e', '673', '6363', 'h', 'q', 'x', 'm', '9505']
[A]: b, c, e, f, h, i, m, n, o, p, q, t, u, w, x, z


[Q]: ['9797', 'h', '9805', 'y', 'd', 'c', 'a', '7229', '3007', 'u']
[A]:
a, c, d, h, u, y