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.

Example Input: ['749', 'r', 'a', 's', 't', '5905', 'm', 'd', '8437', '4583']
Example Output: a, d, m, r, s, t

Example Input: ['7799', '8163', '3389', 'x', 'k', 'm', '6085', 'f', '1131']
Example Output: f, k, m, x

Example Input: ['o', '8271', 'q', '2013', 'v', '7679', '4531', '1405', '4765', '2959', '95', 'y', '7877', 'y', 't', '5489', 'l', '4949', '4929', 'a', 'p', '2769', '5429', '777', 'w', 't', 'v', '3185']
Example Output:
a, l, o, p, q, t, v, w, y