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: ['n', 'y', '7087', '9539', 'x', 'i', 'w', '7237', '8613', 'k', '5999', '4179', 'o', 'm', '7485', '1955', 'w', '1451', 'h']

Answer: h, i, k, m, n, o, w, x, y


Question: ['9345', '345', 'q', 'b', '8049', '2739', '2043', '937', 'q', '1019', 'z', '2937', 'z', '2999', 'n', 'i', 'b', 'l', '2711', '7287', 'b', 'c']

Answer:
b, c, i, l, n, q, z