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: ['r', 'j', '437', 'b', '5223', 'n', 'v', '437', 'd', '8285', 'k', 'j', 'r', 'p', 'n', 'e', 'n', 'j', 'o', '2651', 'j', '6365', 'q', 'q', '2159', 'g', '3641', '7727', 'c', '1197', 's', 't', 'n']

Answer: b, c, d, e, g, j, k, n, o, p, q, r, s, t, v


Question: ['f', '7573', '2067', 'n', '3671', '7969', '7889', '4893', '6501', 'l', 'y', '4331', 'a', 'e', '2081', '3863', 't', 'j', '7921', 's', '7203', '7797', 'f', '4279', '1299', '987', '5003', '9071', '9559', '6061', '1889', '2653', 'm', 'w', '665', '7343', '9763', 'r', '6343', '9393', '9289']

Answer: a, e, f, j, l, m, n, r, s, t, w, y


Question: ['7183', 'k', '7449', 't', '7585', '93', 'z', '3993', '5009', 'l', 'p', '9445', 'm', 'p', 'x', 'q', 'f', 'v', 'r']

Answer:
f, k, l, m, p, q, r, t, v, x, z