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: ['o', 'd', '6495', '5211', '341', 'v', '385', 'v', 'g', 'v', 'l', '7631', '2675', 't']

Answer: d, g, l, o, t, v


Question: ['7989', '6897', 'o', 'v', '5687', '2933', 'w', '8207', 'y', 's', 'w', '3013', 'h']

Answer: h, o, s, v, w, y


Question: ['q', '1703', 'c', 't', '3145', 'e', 'k', '7451', 'r', 'g', 'r', 's', '1005', '3227', '4755', 'z', 'e', 'x', '2529', 'g', '2857', 'u', 'h', '3533', 'r', 'a', 'x', '8995', 'r', 'z', 'r', '627', 'y', 's', 't']

Answer:
a, c, e, g, h, k, q, r, s, t, u, x, y, z