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', 'f', '9567', 'f', '7383', 'k', '599', '1091', '1501', 'y', 'o', 'c']

Answer: c, f, j, k, o, y


Question: ['2047', '4403', 'g', '3017', '1627', 'v', 'r', '2237', '5513', 'o', 'v', '7229', '9801', 'j', '443', 'z', 'q', 'y', '7447', '1659', '3411', '55', '5153', '9921', '2195', '1075', '8187', 'p', 'x', 'h', 'y', 't', 'a', 'r', 'f']

Answer: a, f, g, h, j, o, p, q, r, t, v, x, y, z


Question: ['v', 'd', '3067', 't', '9159', '927', '3335', '9933', 'o', 'h', 'b', 'e', '8029', '4075', '3593', '5249', '8751', 'x', 'z', 'r', '2063', '1197', '6989', 'g', 'y']

Answer:
b, d, e, g, h, o, r, t, v, x, y, z