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: ['c', 'h', '8655', 'r', '7531', 's', 'r', 'w', 'e', 's', 'p', '1709', '5447', 'b', '5855', 'w', 'f', 'i', '7809', 'q', '1975', 'z', '4037', 'k', 'l', 'z', 'g', '9739', '8801', '3405', '6549', '4561', 'd', '1669']

Answer: b, c, d, e, f, g, h, i, k, l, p, q, r, s, w, z


Question: ['2381', 'y', '6631', '5839', 'r', 'm', 'z', 'b', '4663', '595', '7771', '5305', '5087', '3317', '3125', '9551', '4343', '5121', 'm', 'i', '131', '8401', '5379', '1775', 'u', '1125', '9793', '4123', 'h', '1613']

Answer: b, h, i, m, r, u, y, z


Question: ['w', 'p', '7127', '6109', '9127', '2043', '8543', 'o', 'r', 'b', '4009', '5753', 'f', 'v', 'f', 'o', '6515', '4393', 'r', '3653', 'c', 'l', '6047', '1867', 'q', 'p', '6675', '5897', '2511', 'm', 'q', 'w', '8139', 'k', 'l', '8011']

Answer:
b, c, f, k, l, m, o, p, q, r, v, w