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: ['4925', '9943', '7935', '4387', '2449', '5797', 'i', '1517', 'w', 'e', '9525', 'y', 't', 'e', '2793', 'v', '9897', '8709', '7247', 'o', 'f', '5549', 'q']

Answer: e, f, i, o, q, t, v, w, y


Question: ['9403', '9881', '8391', 't', '1793', 'w', 'x', 'y', '6383', 'j', 'r', '5323', 'r', 'l', 'e', 'u', '7193', '2309', '837', 'z', 'w', 'n', '4427', '8269', '6333', 'a', 'p', '1933', '8497', '2665', '1349', '6807', '9009', 'b']

Answer: a, b, e, j, l, n, p, r, t, u, w, x, y, z


Question: ['2985', 'h', '8295', 'o', '7679', 'b', 'z', '6917', '5969', 'i', '9705', '7181', 'b', '235', '2693', '6149', 'r', 'e', '2459', 'l', '9143', '7837', 'c', 'n', 'y', 'p', 'e']

Answer:
b, c, e, h, i, l, n, o, p, r, y, z