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]: ['8311', 'w', 'f', '3431', '9863', '5817', '3969', '2705', 'x', 'm', 'k', 'z', 'z', '235', 'x', '417', 's', 'i', 'y', '8833', '8675', 's', 'm', '2149', '765', 'u', '1021', '7823', 'x', '7275', '3157', 'k']
[EX A]: f, i, k, m, s, u, w, x, y, z

[EX Q]: ['s', 'w', '8949', '4025']
[EX A]: s, w

[EX Q]: ['e', 'v', 'l', '7361']
[EX A]:
e, l, v