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.

['7989', '6897', 'o', 'v', '5687', '2933', 'w', '8207', 'y', 's', 'w', '3013', 'h']
h, o, s, v, w, y

['9783', '3185', '8225', 'u', '1123', 'd', '3453', 'i', '7713', '8457', '8609', 'h', '2767', 'e', '7191', '2929', '1089', '393', 'e', 'd', '11', '9329', '683', '1271']
d, e, h, i, u

['k', 'h', '465', '8899', 'n', '9361', '1857', 'p', 'i', '3365', 'o', '1343', 'v', '8335', '4969', '7693', '5801', '5555', '4263', '6861', 'p', 'a', '4253', 'r', '2031', '2423', 'h', '983', '3365', 'l', '3519', '6029', '7209', 'l', 's', 'x', 'u', '5969', '4849', '8733', '1579', '2925', 'v', 'x']

a, h, i, k, l, n, o, p, r, s, u, v, x