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.

['t', 'r', '2959', '2517', 'a', '9959', '729', '511', 'y', 'r', '465', 'c', '687', 'm', 'b', 'm', '3449', '9713', 'g', '8275', '8823', 'a', 'z', 'w', '2185', '6283', '8457', '8137', '7163', '8329']
a, b, c, g, m, r, t, w, y, z

['4213', '3595', '7937', 'y', '5723', 'v', 'b', '7007']
b, v, y

['6341', '75', 'i', 'q', 'v', 'j', 'v', 'e', '2881', '3193', 'g', 'q', 'z']

e, g, i, j, q, v, z