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.

Input: Consider Input: ['2527', '9123', '8717']

Output: -1


Input: Consider Input: ['5431', 'o', 'u', 'l', 'f', 'd', 'r', '1479', '9357', 's', 'v', '6399', 'b', '7937', 't', '8497', 'r', '131', 'h', 'c', 'v', '8879', 'k', 'r', '4687', 'l', '1065', 'r', 'w', 'l', '3305', '461', 'q', 'h', 'b', 'e', 'e', 'w', '5999']

Output: b, c, d, e, f, h, k, l, o, q, r, s, t, u, v, w


Input: Consider Input: ['x', 'z', 'm', '8011', '4857', '4857', '1631', 'w', 'j', '6049', '6051', '7355', 'u', 't', 't', '2577', 's', 'n']


Output: j, m, n, s, t, u, w, x, z