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', 'f', '9567', 'f', '7383', 'k', '599', '1091', '1501', 'y', 'o', 'c']

Answer: c, f, j, k, o, y


Question: ['w', '8777', 'y', 'e', '8015', 't', 'w', '53', '9149', 'e', 'k', '1837', 'b', 's', '4007', '4905']

Answer: b, e, k, s, t, w, y


Question: ['n', '6559', '117', 'm', '6569', 'e', '3711', 'o', '4601', '4439', 'p', 'g', '977', '8429', 'e', '649', 'n', '9013', '5043', '1861', '7353', '9761', 'd', 'b', '6247', '441', 'd', '2509']

Answer:
b, d, e, g, m, n, o, p