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.
Q: ['1367', 's', 'x', 'e', 'n', '4761', 'o', '5203', '6171', '4445', '1709', 'z', '2075', '1489', '9215', '2687', 'a', 'b', '4693', 'q', '1873', '8617', 'l', 'g', 'z', 'v', 'p', '4579', '9319', '4449', '9895', 'd', '3643', '1457', 'w', 'p', 'g']
A:
a, b, d, e, g, l, n, o, p, q, s, v, w, x, z