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: ['7441', '7967', '2011', '1383', 'i', '3623', 'b', 'y', 'e', '1593', 'r', 'a', 'd', 'b', '6159', '3931', '989', '435', 'o', 'y', 'j', 'w', '7669', 'y', '5781', 'u', '531', '7467', '3971', '8139', 'w', 'a', '5113', '9461', '8377', '7431', '6975', '6055', '7307', 'v']

Answer: a, b, d, e, i, j, o, r, u, v, w, y


Question: ['6455', 'o', 'v', '607', '1639', '7239', 'y', '7075', 'h', '1421', '4783', 'b', '4869', '7229', '4643', 'k', '689', '9233', 'f', 'n', 'h', 'z', '3401', '7779', '383', 'm', 'j', 'h', 'k', '7435', '6521', '9237', 'k', 'e', 'x', 'h', 'l', '5209']

Answer:
b, e, f, h, j, k, l, m, n, o, v, x, y, z