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: ['i', 's']

A: i, s
****
Q: ['s', 'c', 'e', '2457', '9413', 'r', '9949', 's', 'z', 'e', 'a', 'o', '7207']

A: a, c, e, o, r, s, z
****
Q: ['4347', '289', '8557', 'r', 'x', '4079', '83', '5255', '2167', '2379', '1165', 'i', '6977', 'h', '5915', '4963', 'v', 'f', 'q', 'd', 'v', '9533', '4925', '3947', 'c', '2347', 'h', 'c', '2179', 'a', '5461', '6943']

A:
a, c, d, f, h, i, q, r, v, x
****