Given the task definition and input, reply with output. 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.

['1593', 'p', 'v', '2409', 'n', '5397', '3059', '465', '5175', '7875', 'y', '633', 'c', '3413', '5495', 'r', 'e', '7189', 'q', '7319', '5385', '5645', 'v', 'f', 'r', '3093', '4765', 'a', '8719', 't', '1963', '6329', '145']
a, c, e, f, n, p, q, r, t, v, y