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]: ['7367', '9757', '9431', 'h', 'a', 'k', '5833', '6237', 'g', '3585', '8665', 'g', '7517', '1561', 'p', 'p', '1307', '3325', 'q']
[EX A]: a, g, h, k, p, q

[EX Q]: ['3995', 'n', 'z', '8389', '7857', '3005', 'i', 'e', '1117', 'z', '8251', 'r', 't']
[EX A]: e, i, n, r, t, z

[EX Q]: ['8157', 'b', '7747', 'q', '5165', 'u', 'u', 'm', '735', 'l', 'j', 'u', 'd', '1991', 'm', '4135', '4301', 'a', 'w', '2473', '2201', '8891', '5659', '6543', '1339', '5199', 'm', 'c', 'i', 'y', 'q', '1967', '3235', '2189', '3569', '6755']
[EX A]:
a, b, c, d, i, j, l, m, q, u, w, y