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: ['4009', 'y', '9077', 'p', 'q', '6711', '6443', '5491']

Answer: p, q, y


Question: ['h', 'g', 'j', 'i', 'y', '7799', 'y', 'e', 'y', 'e', '6757', '3349', '1213', '191', 'd', '2149', '849', '8325', 'b', '6087', 'w', '7211', '7801']

Answer: b, d, e, g, h, i, j, w, y


Question: ['y', 'q', '4023', 'k', '4625', '765', 'k', '283', 'w', 'q', '6319', 'h', '9235', 'n', '417', 'b', '7933', '6827', '9913', '5849', 'n', '3745', 'c', '4351', '143', '9319', 'b']

Answer:
b, c, h, k, n, q, w, y