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: ['9833', '3383', 'h', '3545', '2899', 'y', 'p', 'q', '1901', '3317', '5641', 'v', 'c', 'u', '5521', 'e', '7997', '2439', '5573', '4119', 'k', '8291', '1009', '8253', '405', '233', 'p']

Answer: c, e, h, k, p, q, u, v, y


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: ['5537', 'e', 'n', '3871', '7439', 'v', 'c', 'a', 'z', 'c', 'w', '9287', 'b', '3173', 'b', 'i', 'q', '6075', 'b', '9533', 'p', '7983', 'k', '4661', '5137', '6449', '9651', '1031', 'o', '6913', 'm', 'c', 'i', '5959', '1791', 'd', 's', 'w', 'l']

Answer:
a, b, c, d, e, i, k, l, m, n, o, p, q, s, v, w, z