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: ['y', 'p', 'q', '2157', 'b', 'w', '8875', 'k', 'i', 'd', '9743', '4941', 'b', 'p', '9941', '495', 'h', 'i', '839', 'c', 'h', 'f', 'b', 'a', 'k', 'z', '7549', '4149', 'h', 'j', '1947', 't', 'f', 'c', '1243']

Answer: a, b, c, d, f, h, i, j, k, p, q, t, w, y, z


Question: ['s', 'j', '6779', '1535', 'd', 'e', 'u', '3023', '241', '9115', 'h', '8003', '3755', 'q', 'm', '2725', 'x', 'y', 'n', 'm', 'j']

Answer: d, e, h, j, m, n, q, s, u, x, y


Question: ['v', 'm', '2473', 'y', 'k', 'w', '8579', 'u', 'b', '8659', 'u', '1427', 'k', 'h', '3729', 'd', '5949', '5503', '3549', '7917', '9449', 'i', '1091', 'e', 'b']

Answer:
b, d, e, h, i, k, m, u, v, w, y