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: ['q', '9033', 'p', 'z', '1743', '247', '967', '445', '9849', 'f', '9113', 'b', 'g', '6041', 'j', '927', 'i', 'p', '6821', 'q', '6701', 'f', 'j', 'o', 'y', 'c', '7981', 'b']

Answer: b, c, f, g, i, j, o, p, q, y, z


Question: ['57', 'j', 'n', '877', 'u', 'w', 'j', 'f', '8977', 'h', '469', '9417']

Answer: f, h, j, n, u, w


Question: ['n', '3201', 'k', '4833', '9899', 'l', '1617', 'w', '8971', '2529', '8373', 'f', '107', 'z', 'q', '4869']

Answer:
f, k, l, n, q, w, z