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]: ['q', 'g', 's', 'g', 'z', '987', '777']
[EX A]: g, q, s, z

[EX Q]: ['v', 'l', 'v', '7673', '8975', 'u', '2471', '4151', '3615', '1139', 'i', 'z', '8833', 'v', '341', 'l', 'n', 'l', 'd', '9207', '1861', '3901', 'a']
[EX A]: a, d, i, l, n, u, v, z

[EX Q]: ['8487', '41', '5649', '4191', '8889', '7081', 'e', 's', 'd', 'w', '8397', 'k', '2055', '4091', '3673', 'z', '415', '4027', '6461', '6843', '3155', '1237', '5525', 'v', '4729', 'h', 'k', 'k', '9623', '2219', '1167', 'r', 'k', '6181', '8343', '8409', '2755']
[EX A]:
d, e, h, k, r, s, v, w, z