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: ['4743', '9687', '2887', '4413', 'r', 'w', '2355', 'l', 'd', '453', 'o', 'm', '4351', '5881', '3963', 'g', 'r', 'z', 'q', '7555', 'y', '9555', '405', 'n', 'l', '6733', '1763', 'v', '9925', 'y', '633', '827', 'w']

Answer: d, g, l, m, n, o, q, r, v, w, y, z


Question: ['1595', '2915', 'o', 't', 'c', 'h', '3969', '5407']

Answer: c, h, o, t


Question: ['c', 'x', '1009', 'd', 'f', '1905', '3949', 't', 't', '1153', '6195', '3067', 'g', '303', 'b', '4985', 'c', 'z', 'b', '7093', 'n', '7175', '205', '5315', '5951', 'p', '8455', '8685', '6531', '3505', 'w', 'n', '8759', 'y', 'g', '5261', 'w', 's', '9883', '3485', 'm']

Answer:
b, c, d, f, g, m, n, p, s, t, w, x, y, z