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: ['4031', 't', 'o', 'c', 'x', '3007', '8329', '6345', '1267', '1017', 'o', 'x', 'l', '4129', 'd', '1987', '487', 'o', 'g', 'j', 'v', 'x', '3983', 'f', 'g', '5759', 'k', 'i', 'o', 'b', 'n', '683', 'j', 'o', 't', '4361', 'u']

Answer: b, c, d, f, g, i, j, k, l, n, o, t, u, v, x


Question: ['653', '1969', '6235', '6283', 'd', 'e', '465', 'e']

Answer: d, e


Question: ['5395', '2443', 'n', '2037', 'p', '5395', 't', '4075', 'k', 'l', 'k', 'j', 'm', '9317', 'r', 'z', '1427', 'a', 'g', 'p', 'c', 'v', 'p', 'v', 'z', 'x', '1171', '317', '9289', '5619', '3743']

Answer:
a, c, g, j, k, l, m, n, p, r, t, v, x, z