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: ['7823', '2933', 'k', '4139', '5585', 'f', 'c', 'm', '2035', 'q', 'z', 'l', '1999', 'q', 'p', '7291', '2091', 'v', '423', 'e', 's', '6089', '4763', '6739']

Answer: c, e, f, k, l, m, p, q, s, v, z


Question: ['d', '2359', '6571', 'c', 'n', 'u', '9513', '9321', '1689', 'b', '969', '1823', 'e', 'b', '9147', 's', '1811', 'k', '5443', '8699', '5483', 'v', 'w', 'n', '1215']

Answer: b, c, d, e, k, n, s, u, v, w


Question: ['u', '9765', '9875', '9337', '293', '335', 'i', '3387', '2723', '4651', '3669', '5711', '7721', 'x', '7693', '5129', '4869', '4011', '9181', '903', '9215', '4881', 'v', '5963', 'r', '3927', '7669', 'm', '3163', '5891', '4285', 'g', 't', '2017', 'c', '1291', 'm', '4399', 'm', 'o', '4079', 'j', 'k', '1249', 'u']

Answer:
c, g, i, j, k, m, o, r, t, u, v, x