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: ['7071', 'h', '837', 'z', 'c', '2217', 'c', '6341', '6607', 'g', '3569', 'a', 'h', 't', 'b', 'f', 'g', 'f', 'l', 'b', 'x', 'o', 'r', '8949', '8071', '1507', 'v']

Answer: a, b, c, f, g, h, l, o, r, t, v, x, z


Question: ['s', 'j', '6779', '1535', 'd', 'e', 'u', '3023', '241', '9115', 'h', '8003', '3755', 'q', 'm', '2725', 'x', 'y', 'n', 'm', 'j']

Answer: d, e, h, j, m, n, q, s, u, x, y


Question: ['d', '3311', '4081', '9397', 'l', 'h', '9803', 'h', '7979', 'v', '1439', '1701', 'y', 'i']

Answer:
d, h, i, l, v, y