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: ['n', 'w', '6735', '3427', '6115', 'q', '7851', '3645', 'g', '6825', '6515', '4885', 'z']

A: g, n, q, w, z
****
Q: ['i', 'i', 'h', 'g', '5123', 'i', 'r', '3183', 'w', 'g', 's', '9777', '455', 'l', 'r', 'h', 'e', 's', 'v', '6823', '463', '9603', 'e', '947', '7071', 'c', '3373', 'j', 'w', 'm', 's', 's', '3483', '9567']

A: c, e, g, h, i, j, l, m, r, s, v, w
****
Q: ['r', 'n', 'l', 'f', 'r', '1279']

A:
f, l, n, r
****