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: ['t', 'a', '2481', '2841', 'a', '2871', 'm', '4435', 'g', '8201', '4351', '9045', 'o']

Answer: a, g, m, o, t


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: ['6129', '6809', 'u', 'x', '5247', '2697', '7095', '7813', '8209', '9491', 'w', '1039', '8439', '1491', 'u', 'y', '3933', '8531', '2675', 'h', '417', '5819', 'k']

Answer:
h, k, u, w, x, y