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: ['4031', 't', 'o', 'c', 'x', '3007', '8329', '6345', '1267', '1017', 'o', 'x', 'l', '4129', 'd', '1987', '487', 'o', 'g', 'j', 'v', 'x', '3983', 'f', 'g', '5759', 'k', 'i', 'o', 'b', 'n', '683', 'j', 'o', 't', '4361', 'u']

A: b, c, d, f, g, i, j, k, l, n, o, t, u, v, x
****
Q: ['2393', 'c', '4413', '5529', '1487', '2499', 'i', 's', 'i', '8575', 'm', 'z', '7179', '6637', '9181', 'z', 'h', '2487', 'i', '3779', '2017', '5217', '5013']

A: c, h, i, m, s, z
****
Q: ['9921', '7201', '77']

A:
-1
****