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]: ['4213', '3595', '7937', 'y', '5723', 'v', 'b', '7007']
[A]: b, v, y


[Q]: ['565', 'i', '615', '3047', 'm', '195', '7547', '3003', '9213', '9063', 'c', '5099', 'v', '5003', '9053']
[A]: c, i, m, v


[Q]: ['e', 'h', 'n', 'u', '6853', 'u', 'w', '1825', '2903', '4481', 't', 'j', '2275', 'n', 'd', '5397', 'i', 'g', '2481', '1983', 'r', '1623', '9391', '9983', '6455', 'e', '2907', '5547', 'a']
[A]:
a, d, e, g, h, i, j, n, r, t, u, w