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: ['3307', 'r', '2665', '3453', 'f', 'd', 'v', '3801', '3153', '3137', 'y', 'i', '9681', 'k', '9253', 'y', 'i', '8631', '2375', '5131', 'r', 'z', '8645', '595', 's', '6749', '2665', '709', '8203']

Answer: d, f, i, k, r, s, v, y, z


Question: ['x', 'z', '9899', 'p', 'd', 'b', '2009', '7609', '1629', 'z', 'r', '657', 'u', 'o', 't', 'l', '4369', '179', '4815', 'y', '5543', '1029', 'o', '2339', 'n', 'm', '6983', '9997', '81']

Answer:
b, d, l, m, n, o, p, r, t, u, x, y, z