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: ['c', 'e', '6509', '1295', 'u', '5445', '1731', '3049']

Answer: c, e, u


Question: ['a', '3281', '9123', '5443', 'w', 'w', 'p', '9275', 'v', 'm', '3549', 'l', 'y', 'l']

Answer: a, l, m, p, v, w, y


Question: ['p', 'i', 'q', '895', '5899', '2163', '5931', 'p', '1667', 'x', '9051', '2865', '3501', '5555', '4559', 'p', '5341', 'l', '8619', '67', 'f', 'q', 'q', '2609', '595', '9075', 'r', '5199', 'v', '3641', 'l', 'r', '5531', '7283', 'n', '5011', '5615']

Answer:
f, i, l, n, p, q, r, v, x