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:
['1801', 'q', '5101', '8863', '2309', 'p', '8789', '9529', '6135', '5523', 'f', '8889', '7639', 'k', '263', '5751', '5529', 'g', '1451', '4143', 'e', '6987']

Ex Output:
e, f, g, k, p, q


Ex Input:
['g', 'x', 'l', 'e', 'd', '1345', '1763', 'm', 'c', '2057', 's', 'a', '4127', 'y', 'h', '8581', 'o', '9203', '4761', 'd', 'u', 'n']

Ex Output:
a, c, d, e, g, h, l, m, n, o, s, u, x, y


Ex Input:
['g', '8591', '4463', '2189', '7901', '1457', 'f', 'i', '9031', 'r', '5519', '3955', 'd', '2093', 'c', 'y', '6591', '6463', 'h', '4371', '111', 'p', '3221', '4185', 'p', '8761', 'w', 'p']

Ex Output:

c, d, f, g, h, i, p, r, w, y