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: ['231', 'r', '5673', 'j', '589', 'z', '4659', 'a', '3763']

A: a, j, r, z
****
Q: ['5761', '2289', '577', 't', '125', 'i', 'g', '9693', '747', 'd', '4829', '9587', 'f', 'k', 'w', 'v', '8607']

A: d, f, g, i, k, t, v, w
****
Q: ['7261', '2209', '5821', 'd', 'q', '7389', '3839', 't', 'w', 'q', 'n', 'f', 'o', '5653', '397', '8929', '9017', '7885', '8211', 'i', '975', '8081', 'v', 'c', '7391', '8921', '2273', 'q', '9305']

A:
c, d, f, i, n, o, q, t, v, w
****