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: ['5859', 'x', 'z', 'v', 'l', 'z', 'g', 't', 'x', '341', '7023', '4937', 'b', 'n', 'y', 't', 's', '1369', '4461', 'f', '1315', 'l', '5221', '6583', 'h', 'j', 't']

Answer: b, f, g, h, j, l, n, s, t, v, x, y, z


Question: ['s', 's', '6581', 'e', '7355', '1315']

Answer: e, s


Question: ['6491', 'o']

Answer:
o