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: ['5499', 'v', '6507', 'w', 'c', '8431', '8861', '5391', '4765', '4295', '1865', '485', '7255', '1205', 'p', 'w', 'q', '6833', '959', 'a', 'i', '2599', '7779', 'h', '9651', 'g', 'r', 'e', 'u', '4511', '1587', '5601', '8287', '5685', 'u', 'g', '2853', 'p', 'k']

Answer: a, c, e, g, h, i, k, p, q, r, u, v, w


Question: ['5463', '5683', 'w', '4071', '3997', 'i', '9677', 'q', 'l', 'v', 'w', '5325', '197', 'g', 'g', '3227', '3477']

Answer: g, i, l, q, v, w


Question: ['o', '3037', 'p', '9679', '3753', '3505', 'q', '2239', 'j', '3653', '9841', 'n', '2401', 'e', 'p', '6527', 'p', '7785', 'n', 'u', '2461', 'y', '6279', 'p', '219', '9113', 'z']

Answer:
e, j, n, o, p, q, u, y, z