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', 'h', 'z', 'n', 'e', 'y', 't', '4371', 'm', '1059', '4853', '8529', 'l']

Answer: e, h, l, m, n, o, t, y, z


Question: ['1985', '729', '169', '1299', 'l', 'z', '6809', '3083', 'w', 'f', '1989', 'z', '889', 'x', 'r', '1601']

Answer: f, l, r, w, x, z


Question: ['8611', '3743', '9657', '6755', 'y', '4557', 'r', 'y', 'i', 's', 'm', 'h', '7069', 'v', 'z', '4785', 'y', '6703', 's', '2031', 'b', 'j', '9247', '3719', '2985', 'q', 'c', 'y', 'p', '4341', 'z', 'a', '5603', '4041', 'z', 'z', 'f', 'l', 'l', 'h', '5461', 'x', '261', '7839', 'u']

Answer:
a, b, c, f, h, i, j, l, m, p, q, r, s, u, v, x, y, z