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: ['u', 'i', '1185', '3795', '5417', 'k', 'b', '2629', '2635', 'z']

Answer: b, i, k, u, z


Question: ['8859', '575', 'l', 'e', '6575', '1303', '8643', '1395', '3171']

Answer: e, l


Question: ['8793', 'n', 'v', 't', '8263', 'i', '3421', 'z', '4485', '963', '6663', '1525', 'p', 'c', '817', '8621', '9657', 'n', '5047', '9655', '3379', 'i', 'l', '4101', 'h', 'f', '3001', '5685', 'n', '4855', 'f', '4383', '8475', 'r', '5463', 's', 'a', '7583', 'l', '1039', '6811', '2967']

Answer:
a, c, f, h, i, l, n, p, r, s, t, v, z