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]: ['x', 'i', 'r', '6011', 't', 'f', 'b', 'i', '8367', '4051', '1459', 'f', '5583', '9609', 'l', 'q', 'g', '8443', 'o', '8697', '7053', '8325', 'k', '7021', 'q', 'm', '6899', '9981', '8985', 'i', 'j', '8043', 'k', '535', '7603', '7629', 'k', '2779', 'g', '2049', 'x', 'd', '8527', 'k', 'q']
[A]: b, d, f, g, i, j, k, l, m, o, q, r, t, x


[Q]: ['s', 'u']
[A]: s, u


[Q]: ['a', '1573', 'l', 'z', '9061', '2811', 'y', 'v', 'o', 'r', '9015', '8121', '8749', 't', 'n', '5477', '3139', 'a', 'c', 'q', '6621', 'n', '2711', '3471', '5767', 'n']
[A]:
a, c, l, n, o, q, r, t, v, y, z