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', '8763', '6399', '45', '6731', 'v', '441', '4763', 'u', '8741', 'r', '9143', 'd', 'p', '2241', 'y', '6523', 'y', 'w', '6771', 't', 'r', '9239', '295', 'z', '461', 'b', '9217', '2597', '1249', 'r', 'i']

Ex Output:
b, d, i, p, r, t, u, v, w, y, z


Ex Input:
['h', 'g', 'j', 'i', 'y', '7799', 'y', 'e', 'y', 'e', '6757', '3349', '1213', '191', 'd', '2149', '849', '8325', 'b', '6087', 'w', '7211', '7801']

Ex Output:
b, d, e, g, h, i, j, w, y


Ex Input:
['5501', '2337', 'z', '4969', '6887', '623', 'l', 'w', 'l', 's', '4817', '1059', '4279', 't', 'o', '1841', '709', '8319', '9037']

Ex Output:

l, o, s, t, w, z