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: ['p', 'f', 'h', '1977', '6221', 'i', 'a', 'l', '5225', '8059', 'c', 'w']

Answer: a, c, f, h, i, l, p, w


Question: ['z', 'l', 's', 'f', 'j', 'x', '1125', 'd', '37', '5009', '9187', 'b', '8683', '8841', 'y', '9955', '1571', 'm', '347', '3679', '5797', '2133', 'g', 'u', '9817', '6347', '2067', '1927', '167', '4215', '45', 't', 'd', '6599', '4751', 'g', 'l', 'u', '7881', 's']

Answer: b, d, f, g, j, l, m, s, t, u, x, y, z


Question: ['e', '2355', '7771', '6671', '6145', '4391', '4763', 'n', 'q', 'b', '1135', 'w', '929']

Answer:
b, e, n, q, w