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: ['v', 'd', '3805', '8031', '3327', 'c', 'n', '6153', '2705', 'w', '5675', '6543', 'm', 'v', 'y', 'd', '2943', '4423', '515', '4501', 'y', '9377', 'j', 'i', 'f', '4749', 'o', 'r', '2605', 'm', '117', 'o', '9197', 't', 'l', '4145']

Answer: c, d, f, i, j, l, m, n, o, r, t, v, w, y


Question: ['l', 'u', '3901', '341', '5801']

Answer: l, u


Question: ['f', 'c', '849', '3405', '7541', '7673', 'p', '187', '2391', 'z', 'x', 'y', 'x', 'k', 'k', '403', 'v', 'e', '8699', 'z', 'i', '5269', '4545', '1179', '9005', '1967', 'u', '809', '3595']

Answer:
c, e, f, i, k, p, u, v, x, y, z