instruction:
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.
question:
['305', '95', 'e', 'q', 'e', '341', 'u', 'w', '5911', '6851', 's', 'u', '2355', 'd', '4151', 'w', '4421', '1129', '8065', 'k', 'q', '3649']
answer:
d, e, k, q, s, u, w


question:
['q', 'h', 'q', '7185', 'f', 'l', 'r', '3605', 'x', 'i', 'v', '8789', 'u', 'x', 'x', '8315', 'x', 't', 'h', 'o', '4943', '5827', '7677']
answer:
f, h, i, l, o, q, r, t, u, v, x


question:
['k', '1299', '1935', 'r', 'h', 'x', 'w', '8871', 'q', '1211', '2247']
answer:

h, k, q, r, w, x