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: ['6599', 'f', 'c', '661', 'q', 'e', '1951', 'f', 'f', 'a', 'd', '9521', '853', 'n', 'w', '6451', '5549', 'k', 't', 'l', 'z', 'm', 'k', '567']

Answer: a, c, d, e, f, k, l, m, n, q, t, w, z


Question: ['2775', '7507', 'c', '4417', '3449', 'y', 'z', 'e', 'f', '9515', '8555', '7269', '8353', '4239', '4347', '4479', '8645', '9925', 'o', 'h', 'o', '8641', 'y', '3251', '1191', 't', 'x', 'z', '7203', 'b', 'b', '7545', '7283', 'z', 'y', '8127', 'x', 'l', '6251', 'y']

Answer: b, c, e, f, h, l, o, t, x, y, z


Question: ['5121', 'l', 'l', '2293', '2025', 'x', 'n', '1477', '5589', 'c', '5391', '4389', '6063', 'v', '9483', '31', '1713', '8939']

Answer:
c, l, n, v, x