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: ['j', '1733', 'p', '6741', '7933', '8943', '733', 'x', '1107', 'z', '1719', '7653', 'y', 'z', '6563', 'p', '4615', 'j', '4489', 'h', 'w', 'y', 'p', 'c', '7949', 'k', 'm', 'r', '9427', '7243', '9777', 'j', '323', '4095', 't']

Answer: c, h, j, k, m, p, r, t, w, x, y, z


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

Answer: b, h, n, u


Question: ['a', 'z', 'c', '7935', '5129', 'q', '275', '6971', '9037', 'k']

Answer:
a, c, k, q, z