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:
['6143', '9073', 'h', '1459', 'q', '5799', '6555', '525', '7921', '5041', '3273', '383', 'd', '9075']

Ex Output:
d, h, q


Ex Input:
['m', '8127', '7519', '4543', '2809', '9855', 'n', '6241', 'w', 'w', 'q', 'w', 'p', '8599', '7819', '3817', 'm', 'q']

Ex Output:
m, n, p, q, w


Ex Input:
['527', 'f', '9913', '7551', 'y', 'h', '8339', '285', '539', '6077', '2269', '7287', 'c', '2313', 'r', '9109', 'j', '4129']

Ex Output:

c, f, h, j, r, y