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: ['4927', 'h', 'x', '4719', 'j', 'f', '7797', 'l', 'i', 'q', 'x', 'i', 'k', '3215', 'k', '1625', 'g', 't', 'i', 'w', 'n', '6659', '8355', '831', 'h', '9723']

Output: f, g, h, i, j, k, l, n, q, t, w, x


Input: Consider Input: ['o', 'l', 'm', 't', '4487', '1019', '9903', 'c']

Output: c, l, m, o, t


Input: Consider Input: ['k', '7391', '3687', 'x', '3091', '4935', 'a', 'x', '4419', 'i', 'q', '551', 'w', '1297', 'c', '9893', 'q', 'k', '351', 'x', '3335', '2641', 'o', '3439', '4031', '707', 's', 'y', '5283', 'm', '4483', 'x', '785', 'p', 'v', '5787']


Output: a, c, i, k, m, o, p, q, s, v, w, x, y