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: ['4835', '9357', '2035', '9225', 'w', '6729', '5413', 'l', 'h', '8977', '1677', '2557', 'h', 'm', '1557', '8979', 'e', '2833', '7361', 'n', 'g', 'g', '9353']
Output:
e, g, h, l, m, n, w