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:
['q', '8149', '4087', '5183', 't', 'j', 'e', 'g', 'r', '2125', 'y', 'l', 'g', '3673', 's', 'r', 'e', 'v', '4259', 'v', '3477', '9353', '3639', 'v', 'n', 'e', 'z', '5071', 'x', '6287', 'e', 'e']

Ex Output:
e, g, j, l, n, q, r, s, t, v, x, y, z


Ex Input:
['7591', '1403']

Ex Output:
-1


Ex Input:
['2375', '7381', '3457', '8697', '4817', '2375', 'n', 'z', '211', '1763', 's', '785', 'g', '7719', 'p', 'x', '1237', 'x', '903', 'b', 'f', 's', '5097', 'w', 'u', 'e']

Ex Output:

b, e, f, g, n, p, s, u, w, x, z