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: ['3627', '2051', '3203', 'c', 'r', 'a', '1453', 'e', 'z', 't', '1093', '4651', 'a', 'f', '8159', '9623', 'l', 't', 'r', '6963', '7071', '8103', '3493', 'y', '2369', '609', '2011', 'f', '187', 'f', 'c']

Answer: a, c, e, f, l, r, t, y, z


Question: ['m', '6761']

Answer: m


Question: ['z', 's', '345', 'h', '7899', '9003', 'z', 'o', 'n', '8223', '9037', 'i', '1281', '5471', 'c', '3117', '2693', 'm', 'y', 'a', 'q', '7695', '3111', 's', 'y', 'c', 'm', 'a', 'g', 'z', 'u']

Answer:
a, c, g, h, i, m, n, o, q, s, u, y, z