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: ['6655', '7445', '1795', '7495', 'h', 'z', 'u', '2199', 'r', 'p', '2245']

Answer: h, p, r, u, z


Question: ['n', 'w', '6735', '3427', '6115', 'q', '7851', '3645', 'g', '6825', '6515', '4885', 'z']

Answer: g, n, q, w, z


Question: ['2603', 'g', 'u', '1161', 'o', 'd', '1703', 'i', '315', '4205', 'g', 'g', '1399', '2995', 's', 'p', '4367', 'a']

Answer:
a, d, g, i, o, p, s, u