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]: ['6027', 'v', 'b', 'l', '7853', 'r', 'y', '2919', '3831']
[A]: b, l, r, v, y


[Q]: ['3035', 'f', 'k', 'e', '3023', 'p', '9667', '5277', '4757', '8433', 'g', '1399', '7721', 'n', 'p', '7469', '7581', '5679', 'g', 'q']
[A]: e, f, g, k, n, p, q


[Q]: ['2667', '9737', 'u', '2595', 'j', 'c', 'e', 'p', '3643', 'h', '5497', 'u', '5175', 'a', 'c', 'r', 'x', '9343', 'k', 'y', 'n', 'q', '8755', '3053']
[A]:
a, c, e, h, j, k, n, p, q, r, u, x, y