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: ['p', 'f', 'h', '1977', '6221', 'i', 'a', 'l', '5225', '8059', 'c', 'w']

Answer: a, c, f, h, i, l, p, w


Question: ['6027', 'v', 'b', 'l', '7853', 'r', 'y', '2919', '3831']

Answer: b, l, r, v, y


Question: ['9449', '881', 'q', '8427', '5305', '7453', 'l', '4519', 's', 'z', '8373', 'p', 'i', 'k', 'c', '9893', 'l', '5865', 'q', 'x', '7187', 'o', '665', 'v', 'd', '369', 'n', 'k', '8369', '1951', 's', 'c', 'm', 'l', 't', 'c', 'r', 'x']

Answer:
c, d, i, k, l, m, n, o, p, q, r, s, t, v, x, z