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:
['u', 'd', '4193', '5687', 'p', 'r', '7787', 't']

Ex Output:
d, p, r, t, u


Ex Input:
['7203', '8715', '3193', 'w', '7159', '8535', 'i', '2425', 'j', 'f', '6709', 'w', 'w', 's', 'e', '9337', 'r', 'r', '5255', '1707', 'u', '1443', 'e', 'e', 'v']

Ex Output:
e, f, i, j, r, s, u, v, w


Ex Input:
['i', 'o', 'u', '3305', '4217', 'w']

Ex Output:

i, o, u, w