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: ['h', '1797', '8211', 'n', 'r', '7707', '2063', '4655', 'x', '5521', '8327', 'g', '7659', 'i', 'x', 'w', '9465', '4625', 'q', '5377', 'r', '225', 'r', 'i', 'e', '4163', 'g', 'g', '3537', 's']

Answer: e, g, h, i, n, q, r, s, w, x


Question: ['f', 't', '2135', '8397', '6361', '389', '2253', 'x', 'p', '4833', '5785', 'x', '1811', '9639', '5739', '175', '3231', '5931', 'r', 'c', 'g', 'h', 'p', '909', 'p', '587', 'a', 'a', 'h', 'q', 's', '5945', '4911', 't', 'h', '7517', 'p', '3177', 'h', 'u', '3577', '7055', 'l']

Answer: a, c, f, g, h, l, p, q, r, s, t, u, x


Question: ['w', 'v', 'v', '7909', 't', '6097', 'u', '9865', '5367', '6691', '3997', '7449', 'r', '3475', 'u', 'z', '9545', '1485', '17', 'n', '2335', '8919', '6601', 'y', '6459', '9025', '2223', 'z', 'p', 'a', 'y', 'm', '5407', 'c', 'j', 'x', 'p', '87', '6599']

Answer:
a, c, j, m, n, p, r, t, u, v, w, x, y, z