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: ['a', '2579', 'f', '6787', '123', '225', '6499', '4419', 'o', '1785', '7981', 'z', 'b', '2441', '2821', 'o', 'k', '2747', 's', 'u', 'q', '3901', '7629', 'k', 'm', 'q', '6577']

A: a, b, f, k, m, o, q, s, u, z
****
Q: ['k', '6595', '1595', 'v', 'h', 'b', '8815', '6681', 'j', '7581', 'p', '9095', '5453', 'r', 'y', '7755', 'x', '1853', 'k', 'q', 'u', 'j', 'q', '9651', 'o']

A: b, h, j, k, o, p, q, r, u, v, x, y
****
Q: ['7359', 's', 'j', '539', 's', 'f', '2159', '3707', 'u', '9911', 'u', '4909', 'n', '8313', '4485', '213', 'y', '4039', 'o', 'x', 'x', '8451', '9495', '9685', 'q', 'w']

A:
f, j, n, o, q, s, u, w, x, y
****