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:
['5161', 'v', 'y', '6005', 'y', 'l', '5451', 'z', 'j', 'd', '4597', '9319', '1241', 'g', 'f', 'b', 'g', '683', '763', 'm']

Ex Output:
b, d, f, g, j, l, m, v, y, z


Ex Input:
['9627', '9879', '5421', '4755', '1533', '6727', 't', '7641', 'd', '3929', 'h', '3989', '8441', 'k', 'p', '2653', 'm', 'b', 'i', '3431', '4907', '5687', 'g', 'h', '9185', '5051', 'k', '7135', '709']

Ex Output:
b, d, g, h, i, k, m, p, t


Ex Input:
['r', '3431', 'e', 'd', '9999', '9749', 'm', 'q', '7933', '8745', '6103', 'z', '3571', '5143', 't', 'o', 'c', 'e', '3761', '6161', '6971', 'l', 'p', 'c', '6485', '41', '6641', 'h', 'i', '2509', '3123', '4453', '5107', 'i']

Ex Output:

c, d, e, h, i, l, m, o, p, q, r, t, z