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', 'w', 'm', 'g', 'c', '5475', '7391', 't', '1049', 'p', 'd', '1397', 'k', 'x', 'j', '2525', 'f', '741']

A: a, c, d, f, g, j, k, m, p, t, w, x
****
Q: ['4905', 'w', '3143', '2217', '573', '1073', '63', 'a', '3971', '2887', '3485', 'y', '3893', '1059', '7623', 'x', 'd', '2991', 'e', 's', '735', 'm', 's', '257', 'x', '5559', '97', 'p', '7237', '693', '7229', 'd', '2311', '807', 'd', 'l', '1247', 'l', '359']

A: a, d, e, l, m, p, s, w, x, y
****
Q: ['l', '4053', '2945', 'u', '4823', '279', 'u', 'l', 'u', '3149', 'x', 'v', 'w', 'b', '2245', 't']

A:
b, l, t, u, v, w, x
****