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:
['5489', 'f', '6833', 's', 'c', '6575', 'w', '2957', '8465', 'v', 'h', '2119', '7731', 'e', '5367', 'e', '3357', 'p', '7565', 'n', 'x', 'n', 'f', '1075', '5941', '6505', 'j', 'p', '2853', 'l', 'q', '4727', 's']
answer:
c, e, f, h, j, l, n, p, q, s, v, w, x


question:
['4945', 'i', 'h', 's', '8925', 'i', '3995', 'f', '813', '1823', '3475', 'q', '2463', '9487', 'c', 'c', 'n', 'y', 's', '6269', 'a', 'u', 'd', 'd', '9291', '3187', '545', '7929', 'd', '1007', '7579', '8421', '4033', 'v', 'c', 'e', 'n', 'j']
answer:
a, c, d, e, f, h, i, j, n, q, s, u, v, y


question:
['v', '3001', 'p', 'b', '7275', '3563', 'q', 'm', 'u', '3935', '3333', 'h', '3687', '3639']
answer:

b, h, m, p, q, u, v