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: ['5499', 'm', '327', 'h', '5765', '4231', 'y', 'g', 's', '883', '9843', '2751', '8967', 'z', '2301', 'l', 'l', 'k', '7843', '7221', '3643', 'k', '5951', 'r', '9441', '235', '3835', 'l', 'e', 'y', '4061', 'l', '1177']

Answer: e, g, h, k, l, m, r, s, y, z


Question: ['4787', 'c', '1727', '9863', '8147', '3931', 'b', '1133', '3023', '7427', '7837', 'n', '7921', 'o', 'c', '3973', '1949', 'x', 'g', 'b', 'd', '8559', '8661', '4465', 'z', '369', 'q', 'e', 'y', '8629', '7665', 'i', 'r', 'n', 'z', '9115', '1393', '4899']

Answer: b, c, d, e, g, i, n, o, q, r, x, y, z


Question: ['k', '6561', 'i', 'n', '5661', '9017', 'l', '9929', 'z', '781', 'b', '1235', '2567', '3487', 'x', '2973', 'x', '645', 'm', '5135', '8049', 'b', '8099', 'c', 'z', '8279', '8207', 'd', 'c', '4953', 'h', '4921', 'z', 'v', '2425', 'm', 'f', '8203', '8781', 'm']

Answer:
b, c, d, f, h, i, k, l, m, n, v, x, z