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: ['m', 'z', 'd', '4667', 'v', '2881', '887', 's', '9861', 'd', '8821', '125', 't', '4493', '6749', '2983', '309', '6033', 'i', '3421', 'j', '4001']

Answer: d, i, j, m, s, t, v, z


Question: ['p', 'g', 'q', 'e', '8045', '9999', '9555', '7995', '7195', 'z', 't', '5223', '3699', 'i', '4797', '3817', 'x', 'y', 'w', 'o', '8915', '7803', 'n', '1117', 'c', '9647', 'p', 'e', '9669', '4845', '9255', '4545', '3693', '6871', 'w', '4327', '3285', 'k', 'f', 'x', 'i', 'b', '5967', '6601']

Answer: b, c, e, f, g, i, k, n, o, p, q, t, w, x, y, z


Question: ['g', 't', '8501', '3881', 'i', '3559', '9789', 'p', '7635', 'x', '91', 'm', 's', '2001', 'c', '8461', 'j', 'z', '7649', 'l', 's', '3473', '1591', 'c']

Answer:
c, g, i, j, l, m, p, s, t, x, z