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:
['z', '3219', '6399', '2357', '7597', '357', 'k', 'k', 'u', 'd', '6115', 'w', '2921', '8809']

Ex Output:
d, k, u, w, z


Ex Input:
['815', '6967', '6553', 'r', 'y', '3641', 'q', 'b', '6131', '4289', 'w', '6093', '6055', 'i', 'b', 'y', '5107', 'v', 'g', '9709', 'x', 'i']

Ex Output:
b, g, i, q, r, v, w, x, y


Ex Input:
['7073', 'r', 'e', '2309', 'k', 'g', 'w', 'b', 'z', '8543', '2165']

Ex Output:

b, e, g, k, r, w, z