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: ['n', 'g', 'u', '2873', 'k', '4411', 'w', '8179', 'w', 'w', 'f', 'g', 'e', '7837', '3055', 'z', 's', '6037', 'n', '1479', 'c', '5311', 'i', 'w', 'z', '1891', '9663', 'y', 'f', 'h']

Answer: c, e, f, g, h, i, k, n, s, u, w, y, z


Question: ['g', '8591', '4463', '2189', '7901', '1457', 'f', 'i', '9031', 'r', '5519', '3955', 'd', '2093', 'c', 'y', '6591', '6463', 'h', '4371', '111', 'p', '3221', '4185', 'p', '8761', 'w', 'p']

Answer: c, d, f, g, h, i, p, r, w, y


Question: ['r', 'c', '7749', 'q', 'n', 'q', 'q', '1819', 'j', 'y', '7193', 'u', 't', '1077', 'e', '7243', '5285', 'h', 'o', 'o', 'n', 'a', 'w', 'j', '405', '7821', 't', 'c', 'j', '8319', '2321', '3917', '7199', 's', 'x', 'q', 'w', 'k', 'v', '1455', 'o']

Answer:
a, c, e, h, j, k, n, o, q, r, s, t, u, v, w, x, y