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: ['163', 'x', 'g', '5997', 'm', 'l', '7225', '7907', '375', 'y', 'a', 'j', 'c', 'j', '7755', '147', 'h', '3845', 'y', 's', 'h', 'u', '8737', '6091', 'j', 'f', 'c', '7395', '881', '1771', 'y', '3691', 'h']

Answer: a, c, f, g, h, j, l, m, s, u, x, y


Question: ['e', '2239', 'l', '8309', 'i', '2613', 'i', '611', '6481', 'j', 'v', '1867', '415', '269', '8053', '3369', 'q', 't', '2303', '7729', '1059', '6135', '3299', 'd', '6855', '207', '6227', '7859']

Answer: d, e, i, j, l, q, t, v


Question: ['347', '7559', '3297', 'k', 'h', '1409', '295', 'x', '1261', '4279', '493', '549', '557', '1471', 'r', 'a', 'l', 'y', '8521', 'q', '9619', '8095', 'p', '3297']

Answer:
a, h, k, l, p, q, r, x, y