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: ['3223', 'h', 'w', 'f', 'y', '1667', '8843', '8759', '9203', '3305', '3549', '5507', '6251', 't', '8319', '9121', '6643', 'u', '4273', '4429', '7543', '7909', '789', '9183', '5729', 'd', '7063', 'b', '6677', 'w', 'x', 'x', 'z', '769', 'p', 'd', 'h']

Answer: b, d, f, h, p, t, u, w, x, y, z


Question: ['o', 'm', '8015', '787', '4787', '1727', 'f', 'e', 'c']

Answer: c, e, f, m, o


Question: ['t', '8733', 'z', 'g', 'a', '171', '3073', 'q', 'm']

Answer:
a, g, m, q, t, z