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: ['1223', 'h', 'a', 'o', 'v', '2535', 'g', '6267', 'w', '9625', '7961', '9577', '7611', '5655', 'p', 'j', 's', '2141', '4101', 'l', '4367', '9383', 'n', '5965', '9097', '7571', 'p', 'u', 'x']

Answer: a, g, h, j, l, n, o, p, s, u, v, w, x


Question: ['2293', 'p', '9787', '7241', '8689', 'u', '3141', 'h', 'c', 'b', 'f', 's', '319', 'c', 'p', '6909', 'p', 'f', '1717', 'd', '2285', 's']

Answer: b, c, d, f, h, p, s, u


Question: ['5523', 'u', '5239', 'm', 's', '1451', 'h', 'j', 'p', 'e', 'a', 'x', 'v', '575', 'o', 'm', '3917', '4989', '8841', '7091', 'q', '9963', '683', 'a', '7077', '1309', '1225', '2531', '5127']

Answer:
a, e, h, j, m, o, p, q, s, u, v, x