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:
['h', 'g', '4563', 'v', 'm', '107']

Ex Output:
g, h, m, v


Ex Input:
['9113', '3625', 'u', '8189', '3649', '259', '5539', '1583', 'g', '4037', 'y', 'v', '8337', 'd', 'q', 'j', 'c', 'h', 'p', '1601', 'z', 'c', 'n', '1767', '1679', '1805', 'm', '4469', '2487', '6015', '973']

Ex Output:
c, d, g, h, j, m, n, p, q, u, v, y, z


Ex Input:
['h', 't', 'd', 'c', '5611', 't', '9971', 'l', 'x', '9841', '1759', 'j', '2175', '5093']

Ex Output:

c, d, h, j, l, t, x