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.

['7989', '6897', 'o', 'v', '5687', '2933', 'w', '8207', 'y', 's', 'w', '3013', 'h']
h, o, s, v, w, y

['d', 'p', 'k', '9679', 'x', 'j', '7481', '1815', 't', 'w', '6513', 'j', '5079', '5219', 'p', '9545', 'a', '1931', '9973', '8125', '5169', '2791', 't', 'd', '2057', 'e', 'x', 'y', '7409', 'u']
a, d, e, j, k, p, t, u, w, x, y

['m', '4779', '5781', '8005', 'p', 'b', 'g', '6269', '7749', 'w', '1229', '4649', '6961', '5269', '2269', '9059', '8383', '677', 'l', '2833', '5953', 'q', 'e', '4969', 'l', 'i', '1405', 'b', 'j', '6037', '9957', 'b']

b, e, g, i, j, l, m, p, q, w