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: ['2943', 'k', '8519', '9103', 'j', '2461', '1049', '2211', '8761', 'l', 'e', '8939', '6013', 'r', '9089', '5781', '5383', '5495', '6699', '7307', '2733', '933', '9865', 'g', '6471', '3179', 'm', '8231', 't', 'e', 'u', '9909', 'g', 'g', '9431', '6521', 'y', 'g', '1415', 'e']

Answer: e, g, j, k, l, m, r, t, u, y


Question: ['477', '3931', 'g', '5967', 'm', '9845', '1607', 'a', '1749', 'k', 'j', '7945', '9125', 'v', 'n', 's', '5185', '1117', '17', 'x', '4149']

Answer: a, g, j, k, m, n, s, v, x


Question: ['3615', '9949', 'v', '4577', 'w', '8641', 'd', '1841', '6823', 'n', '1821', 'v', '1471', 'u', '945', 'k', 'a', '3433', '5231', 'v', '1373', '7411', 'h', '955', '345', '5531', '4553', 'l', 'j', 'k', '5763', 'l', 'd', 'y', '7337', 'q', 'c', '5475', '9903', 'p', '6243']

Answer:
a, c, d, h, j, k, l, n, p, q, u, v, w, y