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: ['5345', 'f', '6605', 's', 'q', 'w', 'p', 'o', 's', 'u', 'i', '7339', '8379', 'h', '9547', 'b']

A: b, f, h, i, o, p, q, s, u, w
****
Q: ['l', '7111', 'd', 'e', 'h', 'z', 'x', '5673', 'v', '8255', 'i', 'z', 'c', 'i', '4287', 'q', '9293', '9137', 'p', 'n', 'o', 'n', '7883', '6453', '7355', '8769', 'y', '9153']

A: c, d, e, h, i, l, n, o, p, q, v, x, y, z
****
Q: ['5415', 'o', 'q', '4723', 'w', '2985', '5925', 'k', 'q', '9827', 'c', '6731', 'i', '5641', 'x', 'b', '165', 'z', 'i', 'p', '159']

A:
b, c, i, k, o, p, q, w, x, z
****