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: ['k', 'c', 'i']

Answer: c, i, k


Question: ['g', '6867', '7965', '3313', 'k', '1827', '7337', 'u', '1209', '5145', 'w', 'h', '9059', 'u', 'b', '3189', '2837', 'k', 'y', 'e', 'b', '4479', '541', '7103', 'h', 'm', '2177', '6377', '3993', '7167', 'q', '2145', '5007', '9135', '5331', 'e']

Answer: b, e, g, h, k, m, q, u, w, y


Question: ['h', '4505', 'n', 'w', 'k', '3585', '2625', '6199', 'b', '7759', '2617', '7617', 'l', '3935', '9061', '4651', '3047', '4411', '4935', '7977', '9153', '5531', 'k', 'f', 'y', '1205']

Answer:
b, f, h, k, l, n, w, y