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]: ['k', 'r', 'f', '4369', 'z', 'z', 'l', '143', 'r', '707', '9167', 'g', '1749', 'i']
[A]: f, g, i, k, l, r, z


[Q]: ['t', 't', 'p', '3245', 'x', 'g', 'i', 'u', '2599', '8613', 't', 'v', 'p', '5635', 'y', '9567', '5193', '8617', 'q', 'f']
[A]: f, g, i, p, q, t, u, v, x, y


[Q]: ['c', '1235', '7261', '181', 'k', 'o', '6697', '9789', '1959', '9077', '2173', 's', 'z', '4221', 'e', 'u', '7467', '893', 'l', '5519', '3775', 'h', '8779', 'm', 'l', '4443', 'u', '185']
[A]:
c, e, h, k, l, m, o, s, u, z