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]: ['3947', '4809', 'b', 'a', '4769', '4179', '535', '5965', 'f', 'j', '2265', 'w', '3103', 'u']
[EX A]: a, b, f, j, u, w

[EX Q]: ['s', 's', '3619', '6051', 'h', '213', '3937', 'v', 'p', 'y', '8449', '9337', '5327', 'a', 'a', 'w', '3985', 'n', 'm']
[EX A]: a, h, m, n, p, s, v, w, y

[EX Q]: ['o', 'j', 'j', '8093', '2069', '7587', 'x', 't', 'u', '9829', '2217', '3095', 'x', '9127', 'q', 'b', '1671', 'd', '495', 'g', 's', '7487', 'u', '3651', '6895', '7259', 'k', 'g', '3031']
[EX A]:
b, d, g, j, k, o, q, s, t, u, x