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: ['277', '8697', 'q', '2023', '5723', 'm', '8673', 'f', 'z', 'z', 'a', '9875', 'p', 'x', 'l', 'z', 'x', '619', '6509', 's', '2067', '571', 't']

Answer: a, f, l, m, p, q, s, t, x, z


Question: ['895', '2049', '8839', '1773', 'v', '467']

Answer: v


Question: ['2361', '8087', '9517', 'f', '1325', '7887', '5361', '2637', '2879', '1531', 'h', '7601', '2081', '3679', 't', 'v', 'd', '9367', 'e', 'i', 'y', '6999', 'o', '7951', 'w', '8827', '3531', '5845', 'g', '55', '1613', 'x', 'z', '9975', '1503', '8191', '3767', '1651', 'p', 'f', '7967', '379', '7699', '6637', '9859']

Answer:
d, e, f, g, h, i, o, p, t, v, w, x, y, z