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: ['6143', 'y', '5505', '9813', 'r', 'v', 'u', '8681', '2387', 'u', 'o', 'm', '9793', 'm']

A: m, o, r, u, v, y
****
Q: ['9403', '9881', '8391', 't', '1793', 'w', 'x', 'y', '6383', 'j', 'r', '5323', 'r', 'l', 'e', 'u', '7193', '2309', '837', 'z', 'w', 'n', '4427', '8269', '6333', 'a', 'p', '1933', '8497', '2665', '1349', '6807', '9009', 'b']

A: a, b, e, j, l, n, p, r, t, u, w, x, y, z
****
Q: ['j', '1059', '3567', 'a', 'x', '3333', 'd', '9397', '8613', '8185', '9863', '6935', '3523', '7827', 'k', '4513', '1539', 'd', '2061', 'j', 'c', 't']

A:
a, c, d, j, k, t, x
****