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: ['2943', 'k', '8519', '9103', 'j', '2461', '1049', '2211', '8761', 'l', 'e', '8939', '6013', 'r', '9089', '5781', '5383', '5495', '6699', '7307', '2733', '933', '9865', 'g', '6471', '3179', 'm', '8231', 't', 'e', 'u', '9909', 'g', 'g', '9431', '6521', 'y', 'g', '1415', 'e']

Answer: e, g, j, k, l, m, r, t, u, y


Question: ['9117', '1153', 'f', 'b', '9979']

Answer: b, f


Question: ['n', 'i', '4589', 'm', 'v', '8583', '549', '709', '3733', 'h', '433', '6183', '3277', 'n', 'v', 'w', 'b', '5635', '8145', 'a', 'i', 'd', 'a', 'i']

Answer:
a, b, d, h, i, m, n, v, w