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]: ['2799', '7519', '345', 'e', 'l', '9369', '4703', '4111']
[EX A]: e, l

[EX Q]: ['e', 'c', '4241', '2685', 'o', '9859', 'z', '2647', 'b', 'c', 'y', '1985', '5985', '5709', '6655', 'q', 'z', '9933', '6817', '6477', '1837', 'x', 'p', '9251', '3787', 'v', '5741', 'e', 'p', '493', '5949', '5519', 'v', 'g', '1403', 'z', 'h', 'z']
[EX A]: b, c, e, g, h, o, p, q, v, x, y, z

[EX Q]: ['4643', '6409', '3809', 'l', 'f', 'x', '1011', '6855', '2629', '4039', 'r', 'l', '4617', 'r', '1661', '9313', 'k', '3279', '8081', '9687', '7857', '9185', 'b', 'o', 'l', 'c', 's', 'i', 'i', 'z', '347', 'b', '1905', 'h', '1449', 'w', 'n', 'n', 'l', 'o', 'f']
[EX A]:
b, c, f, h, i, k, l, n, o, r, s, w, x, z