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.

['4005', '4737', '7417', '185', '6353', 'c', 'g', '9385', 'q', 'o', '5919', 'q', '7641', '1099', 'h', '1373', '5535', 'r', '5633', 'w', 'x', '971', '2147', 'u', 'j', '3235', 'f', '3913']
Output:
c, f, g, h, j, o, q, r, u, w, x