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: ['d', 'g', '9019', '9987', '8713', '9513', 'a', '2043', 'd', '5817', 'w', 'd']

Answer: a, d, g, w


Question: ['1657', 'u', '1849', '425', 'v', '6435', 'j', '2985', '921', '9553', '2621', 'i', '7103', 'd', '8563', 'l', 'b', '6727', '4235', 'n', '8021', 'd', 'z', '437', 'm', '5695', 't', '3421', 'e', 'a', '2941', '791', '1417', '9247', 'h']

Answer: a, b, d, e, h, i, j, l, m, n, t, u, v, z


Question: ['y', 'i', 'n', '9299', '7525', '9259', '1799', 'h', '1391', '465', '839', '285', 'b', 'a', 'o']

Answer:
a, b, h, i, n, o, y