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.

Q: ['1367', 'h', '4153', '1587', 'h', 'b', 'n', 'u', 'n']

A: b, h, n, u
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Q: ['2593', '1835', '5089', 'v', '9723', 'f', '9279', '4257', '2175', '655', 'q', 's', 'v', 'j', 'm', '4471', '6419', '1685', '2793', 'x', '509', 's', '4833', '2125', 'b', '6379', '1075']

A: b, f, j, m, q, s, v, x
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Q: ['9257', '9951', 'b', 'u', '4211', 'c', 'g', 'c', 'z', 'z', 's', 'r']

A:
b, c, g, r, s, u, z
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