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:
['n', 'h', 'h', 'e', 'p', '1265', '4853', '9433', '1227', '1619', '6381', 'o', '8285', 'k', 'u', '7471', 'm', '6887', '6579', '5813', '5563', '8535', 'n', '3743', 'h', 't', '4497', '2791', 'e', 'v', '6769', '7969', 'x', 't', 'x', 'q']

Ex Output:
e, h, k, m, n, o, p, q, t, u, v, x


Ex Input:
['o', 'l', 'm', 't', '4487', '1019', '9903', 'c']

Ex Output:
c, l, m, o, t


Ex Input:
['5071', 'k', '4739', 'n', 'w', '1603', 'q', '6417', '1001', 'e', 'v', '849', '371', '5715', '8703', 'l', '5121', '8465']

Ex Output:

e, k, l, n, q, v, w