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.

Q: ['4009', 'y', '9077', 'p', 'q', '6711', '6443', '5491']

A: p, q, y
****
Q: ['o', '369', 'z', '5721', 'w', 'v', '4973', '7773', 'k', '3071', '5103', '425', '4239', '7977', 'n', 'i', 'k', '8117', '9843', 'n', 'd', '1353', 'h', 'd', 'v', 'z', 'j', '8727', '6997', 'x', '767', '4331', 't']

A: d, h, i, j, k, n, o, t, v, w, x, z
****
Q: ['1421', 'x', 'l', '4939', '3595', 'a', 'o', '4345', '9801', '2001', '1779', 'a']

A:
a, l, o, x
****