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:
['3561', 'd', '9697', 'd', '7761', 'a', '2833', 'c', '2921', 't', '691', 'g', '4797', 'b', '3913', 'f', 'q', '7807', 'j', '3577', 'j', '1775', '2897', '2589', '993', '8595']

Ex Output:
a, b, c, d, f, g, j, q, t


Ex Input:
['5737', 'b', 'e', 't', '7419', 'n', 'y', '5225', '6485', 'b', '1343']

Ex Output:
b, e, n, t, y


Ex Input:
['7529', 'e', '9007', 'u', 'l', 'l', '3751', '441', '5523', '6741', '6629', '9985']

Ex Output:

e, l, u