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.

[EX Q]: ['g', 'p', '2925', 'n', 'o', 'y', '6381', 'l', '4963', 'g', 'm', 'u', 't', '9389', '3787', '7713', '1251', '779', 'i', 'w', '9869', 'y', 'y', '3881', 'k', 't']
[EX A]: g, i, k, l, m, n, o, p, t, u, w, y

[EX Q]: ['r', 'q', '3649', 't', '3941', 'z', '3729', 's', 'g', '6905', 'h', 'v', '1085', '6353', 'a', '9395', '5433', 'a', '2565', 'p', 'a', 'h', '1491', 'j', 'b', 'v', 'e']
[EX A]: a, b, e, g, h, j, p, q, r, s, t, v, z

[EX Q]: ['9791', 'v', 'x', 'l', '1865', 'v', 't', 'k', 'w', '9365', 'y', '3073', '5859', '8689', '8171', '5867', '9325', 'k', 'o']
[EX A]:
k, l, o, t, v, w, x, y