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: ['f', '9203', 'w', 'f', '3751', '8095', '1319', 'f', '3017', 'r', 'y', '8221', '2715', '9959']

Answer: f, r, w, y


Question: ['8301', 'd', 'p', 'l', 'm', '9099', 'o', '8045', 'e', 's', 't', '8853', 'v', '6375', 'q', '2505', 's', '4219', '3587', 'g', '651', '7129']

Answer: d, e, g, l, m, o, p, q, s, t, v


Question: ['j', 'r', '7253', '1999', '8739', '4567', 'x', 'a', 'j', '4385', '5165', 'k', '3167', '771', '7537', 'r', '5589', 'w', '5199', '6863', '8185', '9847', '4495', '6721', 'v', '387', '3435', 'n', 't', 'v']

Answer:
a, j, k, n, r, t, v, w, x