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: ['1653', '3177', 'b', '2785', '2515', 'd', '5513', '5599', '2947', 'v', '2771', '5697', '2913', '4161', '5939', '2655', '6787', '9851', 'q', '3199', 'x', '1305', '9423', '9117', '4821', 'j', '7963', 'i', 's', '469', 'r', 'w']

Answer: b, d, i, j, q, r, s, v, w, x


Question: ['h', 'v', '1263', 'y', '3299', 'd', 'a', 'h', 's', '2007', '7597', '1015', 'k', '6643', '6959', 'g', 'u', 'd', '5737', 'n', 'z', 'y', 'b', 'g', '9059', '7349', 'j', 'w', 'i', 'z', 'p', '5809', 'x', '4421', 'g', '6399', '3965']

Answer: a, b, d, g, h, i, j, k, n, p, s, u, v, w, x, y, z


Question: ['2421', '7269', '5577', '9171', '6739', 'n', '4285', 'd', '3497', '311', '5383', 'q', '9675', 'w', 'm', 'v', '9169', 'g', 's', 'u', '4777', 'w', '9823', '1113']

Answer:
d, g, m, n, q, s, u, v, w