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: ['y', 'b', 'r', 'f', '3745', 'n', '2921', '8133', 'r']

A: b, f, n, r, y
****
Q: ['305', '95', 'e', 'q', 'e', '341', 'u', 'w', '5911', '6851', 's', 'u', '2355', 'd', '4151', 'w', '4421', '1129', '8065', 'k', 'q', '3649']

A: d, e, k, q, s, u, w
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Q: ['235', 'y', '5559', '677', '8577', 'k']

A:
k, y
****