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.

['a', 'a', 'b']
a, b

['3223', 'h', 'w', 'f', 'y', '1667', '8843', '8759', '9203', '3305', '3549', '5507', '6251', 't', '8319', '9121', '6643', 'u', '4273', '4429', '7543', '7909', '789', '9183', '5729', 'd', '7063', 'b', '6677', 'w', 'x', 'x', 'z', '769', 'p', 'd', 'h']
b, d, f, h, p, t, u, w, x, y, z

['h', '9021', 'w', 'p', '9629', 'e', 'z', 'a', 'i', '5207', 's', 'o', 'g', '6905', '7705', '5663', 'b', 'u', '7311', 'p', 'q', 's', 'z']

a, b, e, g, h, i, o, p, q, s, u, w, z