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: ['w', 'i', '4383', '7667', '9617', 'y', 'a', '8051', 'w', '4857', 'y', '3953', 'u', 'o', 'y', 'i', '9201', 'g', '1807', '5367', 'g', '5263', '3995', '6665', '3113', '9433', '6315', 'm', '845', 'x', 'c', 'v', 'h', '1491', 'g', '3519', 'x', 'b', '7695']

Answer: a, b, c, g, h, i, m, o, u, v, w, x, y


Question: ['1429', '7763', '9737', 'l', '1865', 's', '9871', 'e', 'c', 'q', '2727', 'v', 'p', 'd', 'p', '6771', 'c', '7051', 'e', 'b', 'd', 'o', '7427', 'x', 'e', 'm', 'u', '4887', '1649', 'u', 'h', '5249', 'e', '7579', '8549']

Answer: b, c, d, e, h, l, m, o, p, q, s, u, v, x


Question: ['z', '797', '7645', '657', '6809', 'o', 'v', '8195', 'n', '8929', '9591', 'p', '4865', 'i', 'e', '169', 'w', '5989', 'e', 'k', '7221', '6919', 'l', 'q', 's']

Answer:
e, i, k, l, n, o, p, q, s, v, w, z