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: ['4045', '4739', 'd', 'e', '6789', 'e', 'q', '4909', '9511', 'h', '9543', '6725', 'a', '3683', 'q', 'k', 'd', 'q', 'z', 'b', '3245', '9877', '9155', '7751', 'e', '1015', '2379', 'f', 'y', '1121', '9801', 'c', 'h', 'l', 'f', '67', 'v', 'v', 'y', 'c', '3871', 'v', '5893', 'a']

A: a, b, c, d, e, f, h, k, l, q, v, y, z
****
Q: ['9923', 'x', '1901', 'v', '1459', '7503', '3829', '4929', 'k', 'c', '3329', '8793', 'n', 'a', '7249', 'b', 'l', 'l', 'm', 'p', 'b', 'a']

A: a, b, c, k, l, m, n, p, v, x
****
Q: ['3537', 'u', '3865', 's']

A:
s, u
****