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: ['k', '1995', 'b', '2581', 'x', '2639', 'i', '6761', '2701', 'd', '6993', '9375', 'r', 'm', '249', '8115', '8179', 't', '4901', 'i', '6197', '2809', 'e', 's', 'j', '4261', 'f', '6649', '7527', '3839', '5651', '9287', 'n', '2505', 's', 'q', '2825', 'g']

Answer: b, d, e, f, g, i, j, k, m, n, q, r, s, t, x


Question: ['2329', 'i']

Answer: i


Question: ['6919', 's', 'l', 't', '7681', '2933', 'f', 'x', 'q', '4867', '229', 's', '3141', 'z', '1705', '9517', '8525', '2041', 'j', 'x', 'b', '8059', 'y', 'v', 'y', 'r', 'y', '4949', '4419', 'm', '4603', 'y', 'd', 'j', 'u', 'j', 'd', '4257', 'v', '1355', '1703', 'y', '8835', '269']

Answer:
b, d, f, j, l, m, q, r, s, t, u, v, x, y, z