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:
['h', 'g', '4563', 'v', 'm', '107']

Ex Output:
g, h, m, v


Ex Input:
['3117', 'i', 'd', '7537', 'i', 'q', '4649', '7263', '3655', 'd', 'x', '8569', 'g', '2389', '3933', '7099', '563', '3055', '9941', 'm', 'c', '3529', '3577', 'x', 's', 's', '6153', '1731', '9679', 'f', '8839', '5183', '5', '6433']

Ex Output:
c, d, f, g, i, m, q, s, x


Ex Input:
['3471', '5149', '5721', '7277', '2737', '6225', '4367', '4145', '1381', '9791', '8605', '583', 'd', '7773', '4623', 'w', '1275', '987', '541', 'w', 'y', 'r', 'p', '3079', 'm', 'p', '697']

Ex Output:

d, m, p, r, w, y