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: ['j', 'f', '9567', 'f', '7383', 'k', '599', '1091', '1501', 'y', 'o', 'c']

Answer: c, f, j, k, o, y


Question: ['g', '4165', 'n', 'w', 'n', 'e']

Answer: e, g, n, w


Question: ['6221', 'g', 'v', '4373', 'a', '821', 'b', '5533', 'p', 'k', 'u', 'q', 'x', '5133', '4801', '3655', 'l', '5077', '5083', 'g', 'n']

Answer:
a, b, g, k, l, n, p, q, u, v, x