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: ['7777', '6223', 'k', 'k', 'd', '9743', '189', '7705', 'c', '6115', '4275']

Answer: c, d, k


Question: ['f', 't', '2135', '8397', '6361', '389', '2253', 'x', 'p', '4833', '5785', 'x', '1811', '9639', '5739', '175', '3231', '5931', 'r', 'c', 'g', 'h', 'p', '909', 'p', '587', 'a', 'a', 'h', 'q', 's', '5945', '4911', 't', 'h', '7517', 'p', '3177', 'h', 'u', '3577', '7055', 'l']

Answer: a, c, f, g, h, l, p, q, r, s, t, u, x


Question: ['h', 'e', 'i', 'l']

Answer:
e, h, i, l