You will be given a definition of a task first, then some input of the task.
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.

['9677', '9087', 'x', 'j', '2865', '9737', '8917', '3865', '4067', '5759', 'j', '5527', '1583', '4535', 'x', 'o', '5541', '1601', '161', '9539', '3247', '6527', 'w', 'c', '1231', '691', '6173']
Output:
c, j, o, w, x