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: ['q', 'o', '1205', '4429', '6301', 'e', '2857', '5075', '5121', 'p', 'b', '5801', 'a', 'm', 'j', 'p', '1279', '7011', 'x', '2557', 'k', 'v', 'b', 'u', 'w', 'n', '1689', 'o', '1583', 'w', '6403', 'p', '6397', 'e', '823', '5699', 'd', '3399', 'd', 'b']

Answer: a, b, d, e, j, k, m, n, o, p, q, u, v, w, x


Question: ['2453', 'r', 'd', '8499', 't', 's', 'h', 'a', 'm', '9271', 'g', '2599', '6209', 'o', 'i', '4069', 't', '6793', '7679', '6643', '7359', 'm', 'f', 'w', '775', '3347', '6161', '9745', 'i']

Answer: a, d, f, g, h, i, m, o, r, s, t, w


Question: ['9903', '5711', 'p', 's', 'p', '8883', 'v', 'd', '1009', 'p', '9405', 'o', '4103', '2357', 'u', 'c', 'b', 'a', 'p', '4999', 'v', '4227', 'r', 'p', 'y', '5413', '8501', 'u', 't', '8311', '9293', '537', 'a', '6379', 'i', 'v', '7621', 'x', '2643']

Answer:
a, b, c, d, i, o, p, r, s, t, u, v, x, y