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:
['o', '4167', 'b', '1651', '8327', '9219', 'o', 'v', '5841', '6057', 'i', 'q', 'o', 'r', 'a', '7069', 'y', 'h', 'd', '3775', 'j', 't', '3663', '55', '7117', 'e', 'u', 'm', '931', '5777', '8773', '4891']

Ex Output:
a, b, d, e, h, i, j, m, o, q, r, t, u, v, y


Ex Input:
['g', '7517', '3173', 'd', '2143', 'n', '8507', 'l', '8369', '225', 'e', 'l', '9511', 'p', '1317', '5651', 'p', '1125', 't', '739', '6453', 'l', 'g', '8555', '8075', 'x', 's', 'd']

Ex Output:
d, e, g, l, n, p, s, t, x


Ex Input:
['k', 'n', 'b', 'b', 'j', '9435', '865', '3961', '3175', 'y', 'z', '2435', '3891', 'k', '4817', 'u', '5951', '6455', '1305', '777']

Ex Output:

b, j, k, n, u, y, z