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]: ['7055', '2573', '1713', 'x', 'm']
[EX A]: m, x

[EX Q]: ['2181', '7019', 'l', 'z', 'z', 'y', '1245', '4179', '6951', '7249', '2723']
[EX A]: l, y, z

[EX Q]: ['u', 't', 'u', '3601', 'v', 'm', 'o', 'h', '5495', 'b', '9357', '225']
[EX A]:
b, h, m, o, t, u, v