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: ['n', 'h', 'j', '5945', '8511', 'y', '7739', '4717', '2483', 'p', '9545', '7647', '9863', '5591', '5393', 'i', '9225', '589', '1497', 'j', 'm', '2397', 'a', 'd']

Answer: a, d, h, i, j, m, n, p, y


Question: ['8051', 'h', 'g', 's', 't', 'p', 'w', 'x', 's', '8521', 'm', '9719', 'j', 'n', 'i']

Answer: g, h, i, j, m, n, p, s, t, w, x


Question: ['9829', 'u', 'b', 'z', '6561', 'v', 'r', '1663', '3333']

Answer:
b, r, u, v, z