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: ['n', 'h', 'j', '5945', '8511', 'y', '7739', '4717', '2483', 'p', '9545', '7647', '9863', '5591', '5393', 'i', '9225', '589', '1497', 'j', 'm', '2397', 'a', 'd']

Answer: a, d, h, i, j, m, n, p, y


Question: ['z', 'l', 's', 'f', 'j', 'x', '1125', 'd', '37', '5009', '9187', 'b', '8683', '8841', 'y', '9955', '1571', 'm', '347', '3679', '5797', '2133', 'g', 'u', '9817', '6347', '2067', '1927', '167', '4215', '45', 't', 'd', '6599', '4751', 'g', 'l', 'u', '7881', 's']

Answer: b, d, f, g, j, l, m, s, t, u, x, y, z


Question: ['q', 'i', 'b', 's', '1739', '473', 'i', '8103', 'r', '7775', '1945', 'q', 'k', '8935', '4399', '5629', '6899', 'j', 'o', 't', '2527', '1439', 'e', 'f', '2687', 'u', '9119', 'i', 'r', 'i', 'w', '2883']

Answer:
b, e, f, i, j, k, o, q, r, s, t, u, w