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: ['l', 'o', 's', '7411', '7847', '2557', '1977', '2863', '2325', '4177', '4183', '4241', '1005', '1137', '1371', 'v', 'p', 'a', '2453', 'l', '6315', 'l', '6463', 'n', '7645', '9669', '5411', '1631', '5995', 'z', '227']

Answer: a, l, n, o, p, s, v, z


Question: ['2047', '4403', 'g', '3017', '1627', 'v', 'r', '2237', '5513', 'o', 'v', '7229', '9801', 'j', '443', 'z', 'q', 'y', '7447', '1659', '3411', '55', '5153', '9921', '2195', '1075', '8187', 'p', 'x', 'h', 'y', 't', 'a', 'r', 'f']

Answer: a, f, g, h, j, o, p, q, r, t, v, x, y, z


Question: ['z', '8401', '6163', 'm', '6151', 'h', '3601', 'p', '8243', 'w', '9613', '6389', 's', 'e', '1869', 'x', 'i', 'y', 's', '2937', 'h', '3497', '1525', 'm', 'k', 'r', '7987', '2677', '6539', '1101']

Answer:
e, h, i, k, m, p, r, s, w, x, y, z