Detailed Instructions: 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: ['7233', 'a', '9867', 'c', 'u', '2339', '2211', '1373', '9693', 'i', 'x', 'v', '4767', 'w', 'z', 'h', '9175', '5565', 'b', 'f', '8667', '3919', '4785', 'l', '3449', '1909']
A:
a, b, c, f, h, i, l, u, v, w, x, z