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.
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Question: ['k', 'j', 'v', '5277', '8607', 'n', '1109', 'e', 'k', '6579', 'o', '2909', 'u', 't', '9685', '8443', '9257', '8071', 'y', 'b', 'h', '4767', 'a', 'j', '8455', 'b', '7733', '2553', 'e']

Answer: a, b, e, h, j, k, n, o, t, u, v, y


Question: ['x', 'o', '8161', 's', '3653', 'v', 'c', 'e', '5353', 'h', '9145', '333', 's', '7689', '8277', 'a', 'o', 'h', 'z', 'w', '9297', 'w', '9383', '8963', 'k', 'x', 's', 'w', 'h', 'j', '5737', 'o', '2247', '3723', '2043', '4615']

Answer: a, c, e, h, j, k, o, s, v, w, x, z


Question: ['2569', '4287', '2377', '5429', 'n', 'e', '5725', 'n', '4371', '4663', 'q', 'w', 'n', '3545', 'a', '9411', 'r', 'y', 'u', '3317', 'l', 'v', '3401', 'e', '781', '4385', '2977', 'g', '2571']

Answer:
a, e, g, l, n, q, r, u, v, w, y