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:
['5499', 'm', '327', 'h', '5765', '4231', 'y', 'g', 's', '883', '9843', '2751', '8967', 'z', '2301', 'l', 'l', 'k', '7843', '7221', '3643', 'k', '5951', 'r', '9441', '235', '3835', 'l', 'e', 'y', '4061', 'l', '1177']
answer:
e, g, h, k, l, m, r, s, y, z


question:
['j', '425', '6223', '6631', 'y', '7649', 'r', 'a', '7933', '7947', 'l', 'l', '8755', 'g', 'b', '3351', '49', 'v', 'm', 'x', '3291', '1007', '1401', 'z', 'q', 'a']
answer:
a, b, g, j, l, m, q, r, v, x, y, z


question:
['t', 'p', 'm', 'h', 'y', '4809', '1241', '8907', '689', '4097', '2295', '8571', '7857', '4215', 'z', 'i']
answer:

h, i, m, p, t, y, z