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: ['f', '6817', 'f', 'd', '3835', '3051', 'u', 'l', '7679', 'b', '3931', '1441', 'q', '8675', 's', '5487', 'y', '2279', 'x', 'y', '9513', '2875', '1771', '879', '2927', '3469', 'v', 't', 'k', '9991', '2565', '7345', '973', 'w', 'i', '6105']

Answer: b, d, f, i, k, l, q, s, t, u, v, w, x, y


Question: ['l', '7111', 'd', 'e', 'h', 'z', 'x', '5673', 'v', '8255', 'i', 'z', 'c', 'i', '4287', 'q', '9293', '9137', 'p', 'n', 'o', 'n', '7883', '6453', '7355', '8769', 'y', '9153']

Answer: c, d, e, h, i, l, n, o, p, q, v, x, y, z


Question: ['8347', '6703', '6689', 'e', 'f', '2129', '9287', 'f', '6669', 'w', '3991', 'n', '4941', 'b', '641', '113', '9335', 'g', '9545', 'x', '885', '5109', 'k', 'c', '5093', '2035', 'v', '5171', 't', 'k', 'o', '8573', 'z', 'n', '8567', 's', '1167', '2305', 't', 'i', '5963', 'j', '8689', '6327', 'z']

Answer:
b, c, e, f, g, i, j, k, n, o, s, t, v, w, x, z