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.

Ex Input:
['5761', '2289', '577', 't', '125', 'i', 'g', '9693', '747', 'd', '4829', '9587', 'f', 'k', 'w', 'v', '8607']

Ex Output:
d, f, g, i, k, t, v, w


Ex Input:
['8315', 'b', '4333', 'f', '6507', '6211', '3475', 'c', 'e', '8039', '661']

Ex Output:
b, c, e, f


Ex Input:
['7437', '4661', 'c', '7273', 'd', 'c', 'u', '9231', '6523', '9119', 'u', '7133', '7781', 'e', '6131', 'z', '1141', '8369', '717', 'j', 'z', '3309', 'd']

Ex Output:

c, d, e, j, u, z