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: ['1707', '381', '3957', '7853', '4987']

Output: -1


Input: Consider Input: ['5089', '6113', 'v', 'l', '5529', 'q', '7499', 'e', 'r', 'c', '5999', '2619', 'a', '2523', '7697', 'j', 'c', '6537', '8313', '5623', '4225', '7677', 'q', 'a', '6559', 'y', 'b', 'm', '7645', '7019', 'r', 'i', '5225', '703', 'i', '6189', 'f', 't', '7553']

Output: a, b, c, e, f, i, j, l, m, q, r, t, v, y


Input: Consider Input: ['u', '6757', '2645', '7813', '1787', '2819', '2427', 'n', 'b', '6953', 'm', '9361', 'm', 'n']


Output: b, m, n, u