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]: ['a', 'w', 'm', 'g', 'c', '5475', '7391', 't', '1049', 'p', 'd', '1397', 'k', 'x', 'j', '2525', 'f', '741']
[EX A]: a, c, d, f, g, j, k, m, p, t, w, x

[EX Q]: ['3995', 'n', 'z', '8389', '7857', '3005', 'i', 'e', '1117', 'z', '8251', 'r', 't']
[EX A]: e, i, n, r, t, z

[EX Q]: ['9803', 'n', '1623', '5105', 'x', 's', '9399', 'f', '9531', 'e']
[EX A]:
e, f, n, s, x