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: ['4423', '8295', 'h', '4881', 'j', 'c', '1185', 'z', 'm', '2725', 'p', '9187', '6275', '1617', '2523', '9879', '4149', '2197', '3909', '5155', '691', 'r', 'e', 'u', 'l', 'd', '1581', '2763', 'c']

Answer: c, d, e, h, j, l, m, p, r, u, z


Question: ['1653', '3177', 'b', '2785', '2515', 'd', '5513', '5599', '2947', 'v', '2771', '5697', '2913', '4161', '5939', '2655', '6787', '9851', 'q', '3199', 'x', '1305', '9423', '9117', '4821', 'j', '7963', 'i', 's', '469', 'r', 'w']

Answer: b, d, i, j, q, r, s, v, w, x


Question: ['4611', 'n', 't', 'e', 'y', 't', '3057', '7747', 'b', '1551', 'l', 'd', 'y', '631', 'l', '6727', '727', '471', '2793', 'y', 'x', 'i', '1295', '2631', '281', 'b', '3387', 'x', '9653', 'i', 'z', '8899', '2731', 'g', '3827', '6879', '1403', '6751', '6699', '7123', '1021', '6661', 'a']

Answer:
a, b, d, e, g, i, l, n, t, x, y, z