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.

['2161', '8009', '3057', 'r', '3897', 'd', 'j', '2727', 'b', '3231', 'i', '9227', '393', '5799']
b, d, i, j, r

['r', '4655', 'm', 'l', '4371', 'o', '5331', '5469', 'j', 'u', '4915', 'v', 'i', 'f', 'j', '6139', 'y', '2423', '1271', '2289', '5565', '7561', '9697', 'e', 's', 'u', '9581', 'y', '6095', '5047', '625', '9047', 'd', 's', '8307', '3615', '8145']
d, e, f, i, j, l, m, o, r, s, u, v, y

['4963', 'm', '3967', 'c', '4687', 'g', '5375', 'a', '9987', 'x', '4489', '9043', 'w', 'i', '1423', '3469', 'e', 'w', '8081', '1583', '1955', 'w', 'u', 'k', '5449', 'p', 'i', 'y', '7319', '9377', 'h', '4541', '9061', '529', '5777', 'f']

a, c, e, f, g, h, i, k, m, p, u, w, x, y