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: ['j', 'a', 'z', 'h', '4129', '4159', 'm', 'o', 'o', '1193', '2905', '3083', 'q', 't', 'm', 'o', '673', '7547', 'n', 'c', 'r', 't', '2897', '4959', 'z', '2377', 'y', '7977', 'u', 'b', 's', 'w', 'e', 'd', '8051']

Answer: a, b, c, d, e, h, j, m, n, o, q, r, s, t, u, w, y, z


Question: ['2393', 'c', '4413', '5529', '1487', '2499', 'i', 's', 'i', '8575', 'm', 'z', '7179', '6637', '9181', 'z', 'h', '2487', 'i', '3779', '2017', '5217', '5013']

Answer: c, h, i, m, s, z


Question: ['5971', 'x', 'c']

Answer:
c, x