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: ['1945', 't', '4477', '4439', '6569', '2021', 'y', 't', '2725', '8947', '6921', '1373', '8107', 'g', 'c', 'w', 'x', 'b', '9117', 'k', '6567', '5073', '2307', 'e', 'b', '7405', 'e', 'x', '1419', 'd', 'o', 'n', 'a', '2647', 'z', '1459', 'n', '6137', 'u', 'b', 'q', '4459']

A: a, b, c, d, e, g, k, n, o, q, t, u, w, x, y, z
****
Q: ['h', 'g', '4563', 'v', 'm', '107']

A: g, h, m, v
****
Q: ['4005', '4737', '7417', '185', '6353', 'c', 'g', '9385', 'q', 'o', '5919', 'q', '7641', '1099', 'h', '1373', '5535', 'r', '5633', 'w', 'x', '971', '2147', 'u', 'j', '3235', 'f', '3913']

A:
c, f, g, h, j, o, q, r, u, w, x
****