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.

Ex Input:
['747', '5385', '5313', 'p', '9581', 'r', '1339', '3919', 'e', 'e', '8057', '7739', 'i', 'e', '3311', '963', 'g', 'h', '7349', 'y', '1493', 'e', '3055']

Ex Output:
e, g, h, i, p, r, y


Ex Input:
['815', '6967', '6553', 'r', 'y', '3641', 'q', 'b', '6131', '4289', 'w', '6093', '6055', 'i', 'b', 'y', '5107', 'v', 'g', '9709', 'x', 'i']

Ex Output:
b, g, i, q, r, v, w, x, y


Ex Input:
['3183', 'k', '6957', 'p', '485', '1125', 'q', 'b', '5885', 'i', '2209', '8613']

Ex Output:

b, i, k, p, q