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: ['1487', '8003', 'd', '7237', 'l', 'y', '2749', 'e', '9685', '2825', 'z', '7743', 'r', '9617', 'w', '4323', '2173', '8419', '2831', '8923', 'l', '2985', '303', 'y', '9409', 'i', 'h', 'e']

A: d, e, h, i, l, r, w, y, z
****
Q: ['j', 'r', 'z', 'f', '1485', '2419', 't', 'd', '6023']

A: d, f, j, r, t, z
****
Q: ['6243', '9049', '7497', 'a', 's', '6263', '6285', '309', '4777', 'q', 'd', 'x', 'e', '9633', 'c', '9527', '6049', '2299', '4939', '3565', 'r', '4465', '5345', 'b', 'b', 'b', 'a', '5921', '869', 'r', 'x', '8917', 'm', 'u']

A:
a, b, c, d, e, m, q, r, s, u, x
****