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: ['p', 'g', 'q', 'e', '8045', '9999', '9555', '7995', '7195', 'z', 't', '5223', '3699', 'i', '4797', '3817', 'x', 'y', 'w', 'o', '8915', '7803', 'n', '1117', 'c', '9647', 'p', 'e', '9669', '4845', '9255', '4545', '3693', '6871', 'w', '4327', '3285', 'k', 'f', 'x', 'i', 'b', '5967', '6601']

Answer: b, c, e, f, g, i, k, n, o, p, q, t, w, x, y, z


Question: ['z', 'l', '1759', 'k', '8197', 'v', '931', '2587', '7219', '3455', 'e', '8135', 'm', 'n', 'm']

Answer: e, k, l, m, n, v, z


Question: ['p', 'r', '9291', '7313', '1073', '5675', 'd', 'j', 'p', '2359', '4887', '5257', '5843', '3127', 'a', 'q', 'l', 'u', 'o', 'y', 'u', 'h', '3981', '2773', '7367', '6427', 'v', '8919', '6245', 'e', '5937', '5859', 'r', 'c', '7157', '833', '3361', '497', 'q']

Answer:
a, c, d, e, h, j, l, o, p, q, r, u, v, y