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: ['o', '369', 'z', '5721', 'w', 'v', '4973', '7773', 'k', '3071', '5103', '425', '4239', '7977', 'n', 'i', 'k', '8117', '9843', 'n', 'd', '1353', 'h', 'd', 'v', 'z', 'j', '8727', '6997', 'x', '767', '4331', 't']

Answer: d, h, i, j, k, n, o, t, v, w, x, z


Question: ['4123', '1397', '103', 'w', 't', 'j', '233', '7239', 'b', 'n', 't', '6273', 'l', '1167', '8389', '5609', '9029', '7741', 'o', 'p', '6547', '5593', 'd', '8401', 's', '4243', 's', 'u', 'm', '6659', '5691', '2105', '8897']

Answer: b, d, j, l, m, n, o, p, s, t, u, w


Question: ['p', 'g', 'e', 'q', '9363', '6631', 'm', 'x', 'p', 'h', 't', '5143', 's', '9109', '8799', 'v', '8739', 'p', '6289', '9629', '9107', '4577', 'a', 'q', 'f', 'f', 'j', '7855', 'k', 'q', '8431', 'c', '3847', '3849', 'c', '9029', 'p', '7575', 't', '2737', 'c', 'h', 'h', 'b']

Answer:
a, b, c, e, f, g, h, j, k, m, p, q, s, t, v, x