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: ['4031', 't', 'o', 'c', 'x', '3007', '8329', '6345', '1267', '1017', 'o', 'x', 'l', '4129', 'd', '1987', '487', 'o', 'g', 'j', 'v', 'x', '3983', 'f', 'g', '5759', 'k', 'i', 'o', 'b', 'n', '683', 'j', 'o', 't', '4361', 'u']

Answer: b, c, d, f, g, i, j, k, l, n, o, t, u, v, x


Question: ['e', '1251', 'y', '6689', '6389', 'h', 't', '503', '5093', 'e', '923', '7051', 'm', 'u', '4501', '3289', '6887', '8341', 'o', '3671', 'n', 'w', '7749', 's', 'j', 'o', '8429', 'q', 'v', 'p', 'd', 'g', 'i', 'f']

Answer: d, e, f, g, h, i, j, m, n, o, p, q, s, t, u, v, w, y


Question: ['3205', 'u', 'z', '2505', '9675', '6623', '3625', 'k', '3309', '4429', 'r', 'h', 'y', 'n', '305', '1037', '107', 'w', 'f', 'w', '9403', '5105', '4953', 'k', 'k']

Answer:
f, h, k, n, r, u, w, y, z