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.

[Q]: ['v', '3765', '4065', 'a', '4201', 'f', 'x', '9275', 'q', '9303']
[A]: a, f, q, v, x


[Q]: ['f', '217', '449', 't', 'j', '4097', '5561', '8317', '647', 'u', 'b', '7833', 'r', '9011', 'z', '2753', '2183', 'z', 'o', 'g', '7541', 'b', '8795', '327', 'v', 'e', 't', 'l', '4909', 'k', '7681', 'r']
[A]: b, e, f, g, j, k, l, o, r, t, u, v, z


[Q]: ['6869', '5205', '9543', 'q', '3527', '5897', 'i', 'n', '6255', 'f', 'v', 'u', 'c', '9555', '6705', '6339', 'z', '4595', '9425', 'f', '2395', 't', 'c', '7071', '7063', 'p', '5131', '6637', 'o', '2165', '961', '4345', 'd', 'x', 'n', 'g', '6023', '8229', '2157', '861', '1987', 'n', '8901', '6635']
[A]:
c, d, f, g, i, n, o, p, q, t, u, v, x, z