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: ['z', '3219', '6399', '2357', '7597', '357', 'k', 'k', 'u', 'd', '6115', 'w', '2921', '8809']

Answer: d, k, u, w, z


Question: ['l', 'o', 's', '7411', '7847', '2557', '1977', '2863', '2325', '4177', '4183', '4241', '1005', '1137', '1371', 'v', 'p', 'a', '2453', 'l', '6315', 'l', '6463', 'n', '7645', '9669', '5411', '1631', '5995', 'z', '227']

Answer: a, l, n, o, p, s, v, z


Question: ['h', '1459', 'a', 'l', '6469', '2713', 'i', '3765', 'e', '9769', '9637', '8369', 'y', 'w', 'o', '4625']

Answer:
a, e, h, i, l, o, w, y