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: ['7203', '8715', '3193', 'w', '7159', '8535', 'i', '2425', 'j', 'f', '6709', 'w', 'w', 's', 'e', '9337', 'r', 'r', '5255', '1707', 'u', '1443', 'e', 'e', 'v']

Answer: e, f, i, j, r, s, u, v, w


Question: ['8815', 'w', '8629', 'y', '3891']

Answer: w, y


Question: ['w', '1985', 'e', '7557', 'f', 'v', 's', 'l', '8429', 'x', '8655', 'v', '1573', '9041', 'y', 'c', '8419', 'e', '2101', '1859', 'x', 'k', '6645', '3263', '6133', 'r', '509', 'b', '8769', 'n', 'c']

Answer:
b, c, e, f, k, l, n, r, s, v, w, x, y