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: ['x', 'i', 'k', 'c', 'f', '3057', '481', '5887', '847', 'c', 'x', 't', 'g', '5805', 'a', 'i', '2885', '403', 'x', 'c', '4815', '2765', 'c', '5181', 'l', 'e', '3843', '1171', 'u', '7867', 'z', 'e', '9349', '5011', 'h', 'x', '3193', 'i', '4595', '8621', '6007', '1879']

Answer: a, c, e, f, g, h, i, k, l, t, u, x, z


Question: ['b', 'd', '8153', 'u', '3695', '5317']

Answer: b, d, u


Question: ['n', '4039', '4011']

Answer:
n