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: ['4945', 'i', 'h', 's', '8925', 'i', '3995', 'f', '813', '1823', '3475', 'q', '2463', '9487', 'c', 'c', 'n', 'y', 's', '6269', 'a', 'u', 'd', 'd', '9291', '3187', '545', '7929', 'd', '1007', '7579', '8421', '4033', 'v', 'c', 'e', 'n', 'j']

Answer: a, c, d, e, f, h, i, j, n, q, s, u, v, y


Question: ['w', '8777', 'y', 'e', '8015', 't', 'w', '53', '9149', 'e', 'k', '1837', 'b', 's', '4007', '4905']

Answer: b, e, k, s, t, w, y


Question: ['8479', '3711', 'e', '3603', 'i', 'a', '6983', '9', 'o', 'a', 'e', 'a', 'm', '55', 'j', '6213', '311', 'm', '9401', '8829', '1967', 'f', '6053', 'i', 'm', '7089']

Answer:
a, e, f, i, j, m, o