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.
Input: ['5465', '7029', 'n', 'f', '7451', 'w', '1023', 'w', 'x', '507', 'f', 'z', '4127', '3113', '7209', 'c', 'h', '1115', '599', 'f', '3383', 'h', 'c', 'a', 'h', '1027', '6531', '9133', '9061', 'b', '2711', 'i', 'a', '5239', '1431', 'r', '4561']
Output:
a, b, c, f, h, i, n, r, w, x, z