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: ['6209', 'x', 'j', 'w', '7965', '4905', '6297', '4291', '7183', 'a', 'l', '5267', 'r', '5935', 'a', '7865', 'h', 'p', '6117', 'a', 'y', 'y', 't', 'v', '7271', 'e', 'e', 'z', 'i', 'l', '4731', '2059', 'm', '5703', 'k', 'f', '8125', 'e', '7569', 'r', '2287', '593']

Answer: a, e, f, h, i, j, k, l, m, p, r, t, v, w, x, y, z


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: ['2133', '6301', 'k', '2325', '581', '5107', '789', 'r', 'x', '1559', '3203', '6109', '5599', '3383', '785', 'j', '1875', '7653', '9739', '9089', 'y', '8865', '9795', '8367', '5347', 'm', 'z', 'm', '5025', 'h', '205', '269', '379', 'p', '7927', 's', '8035']

Answer:
h, j, k, m, p, r, s, x, y, z