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: ['r', '9489', 'e', 'n', '6323', 'd', '3163', '265', '8587', '7891']

A: d, e, n, r
****
Q: ['g', 'h', 'g', 'g', 's', 'h', '2849', '2705', '1185', 'x', '5789', '8221', 'e', 'x', 'g', 'b', '4903', 'q', '1563', 'r', 'k', 't', '9047', 'p', 'p', '9397', 'u', '7473', 'f', 'o', 'y', '1957', '1039', '9905', 'i', '4829', 'q', 'w', 'k', 'p', 't', '563', 'g', 'l']

A: b, e, f, g, h, i, k, l, o, p, q, r, s, t, u, w, x, y
****
Q: ['q', '1569', 'q', '5439', '3183', '1511', '1337', '6367', '9367', 'x', 'w', '1567', 'a', 'z', '33', '4309', 'b', '5611', '21', 's', 'u', '4309', 'd', '4873', '1555', '6107', '5693', 'g', '4961']

A:
a, b, d, g, q, s, u, w, x, z
****