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: ['w', '5341', 'b', '6243', 'v', '877', '1087', '6763', '5241', '3369', '9119', 't', 'v', 'j', '8261', 'o', 'b']

Answer: b, j, o, t, v, w


Question: ['7595', '5303', '3985', 'n', 'w', 's', 'r', 'f', '8237', 'q', 'y', 'f', '3121', '2463', '4597', 'q', '6801', 'f', 'i', '8563', '3267', 'k', '6157', 'f']

Answer: f, i, k, n, q, r, s, w, y


Question: ['3595', '6209', '8755', 'n', '9201', '8307', 'f', '4171', '667', '8661', 'k', 'i', '8487', 'r', 'c', 'w', '4979', 'c', '6457', 'd', 'r']

Answer:
c, d, f, i, k, n, r, w