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: ['2313', '2073', 'd', 'e', 'o', '793', '4999', 'f', 'c', '4473', '4519', 'u', 'n', 'k', '69', '475', 'a', 'j', 'q', 'x', '5869', '9523', 'z', 'v', '9265', '5989', 'p', 'm', 'g', 'y', 'b']

A: a, b, c, d, e, f, g, j, k, m, n, o, p, q, u, v, x, y, z
****
Q: ['q', 'c', 'o', 'e', 'n', 'q', 'w', '9475', 'w', '863', 'r', '2219', '3483', '5035', '8209', '7957', 'b', '3735', '1423', 'l', '3409', '7639', 'd']

A: b, c, d, e, l, n, o, q, r, w
****
Q: ['r', '2945', 'a', '6555', '3189', 'd', '7991', '2385', 'm', '3335', '6631', 'b', 'b', '8627', 'd', '9383', 'l']

A:
a, b, d, l, m, r
****