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.
Problem:['7867', 'f', 'k', '8509', 'q', 'r', '9693', '3551', 'p', 'j', '703', 'd', 'e', '1679', 'o', '373', 'k', 'e', 'l', '8697', 'j', '241', 'i', 'a', 'f', '4565', '7303', 'o', 'x', '3153', 'w', '9107', '5591', '1625', 'g', '687', 'g', '7875', '203']
Solution:
a, d, e, f, g, i, j, k, l, o, p, q, r, w, x