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: ['j', '8797', 'i', '5443', 'i', 'f', '7593', 'u', 'h', '3251', 'l', '681', 'y', 'n', 'r', '1699', '1379', '8987', '6955', 'x', 'p', 'x', '553', 'q', '5679', 'q', 'w', '9007', 'r', '8945', '7351', 'a', 'v', 'k', '1309', 'v', 'i', '4161', 'a', 'q', '2919', '6917', '6845']

Answer: a, f, h, i, j, k, l, n, p, q, r, u, v, w, x, y


Question: ['9385', '4021', 'y', '9629', 'u', '7623', 'd', '5155', 'x', '2605', '8893', 'l', 'p', 'a', 'm', '6699', 'i', '4503', '6623', 'm', 'l', '6115', 'p', 'w', '9691', '811', '4769', '2659', 'x', 'c', '6513', '5499', 's', 'q', 'f', 'v', 'z', 'w', 'z', '1361']

Answer: a, c, d, f, i, l, m, p, q, s, u, v, w, x, y, z


Question: ['t', '3375', 'l', '6139', '7357', '525', 'v', '1061', 'q', 'p', 'i', '1433', '177', '8773', '8055', '8249', '7573', 'n', '9945', 'd', '1049', 'f', '9185', 'j', 'm', '9661', 's', 'j', 'h', 'u', 'n', 'u', 'o', '4715', 'o', 'o', '3195', 'u']

Answer:
d, f, h, i, j, l, m, n, o, p, q, s, t, u, v