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: ['c', 'a', 'p', 'p', '4203', '1587', '2953', '9809', '99', '5821', 't', 'i', '4213', '1809', 's', 'l', 'i', 'b', '9233', '3983', '7713', '1807', 'k', 'f', '7825', '5491', 'o', '1347', 'u', 'h', '3967', 'u', 'g', '6775', '1069', '9211', 'i', '3369', 'r']

Answer: a, b, c, f, g, h, i, k, l, o, p, r, s, t, u


Question: ['575', 'u', 'c', '8113', '2853', '3661', '9427', '3071', '4069', '835', 'w', 't', 'w', 't', 'v', 'g', 'c', '5497', '1703', '8433', 'g', '3545', '2887', 'z', 'a', '2241', '5799', '5915', 'u', '4015', '8327', 'z', 'a', 'w', '8311', '289', '8575', 't', 'b', '2873', 'r', 'z', 'x', '1165', '9881']

Answer: a, b, c, g, r, t, u, v, w, x, z


Question: ['3939', 'h', 'g', '5887', '5997', '2843', '1501', '3815', '4749', 's', '9127', 'd', 'z', '4063', '5007', '1335', '4879', 'c', '7423', '8331', '2237', '4701', '3821', 'g', '665', '2561', 'a', '6283', 'q', 'k', '2515', 'l']

Answer:
a, c, d, g, h, k, l, q, s, z