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:
['1593', '8165', 'q', '6689', 'b', 'r', '373', 'g', '6505', '415', '495', 'j', 'j', 'f']

Ex Output:
b, f, g, j, q, r


Ex Input:
['1749', 'i', 'w', 'j', '3171', '1999', '1037', '4937', '7013', '3593', '287', 'o', 'i', 'j']

Ex Output:
i, j, o, w


Ex Input:
['s', '7545', 'e', '6179', 'z', 'u', 'b', 'f', '9363', 'l', 'j', '5277', '2289', '3287', 'x', '6019', '5353', 'l', '4285', 'm', '9659', 'p', 'z']

Ex Output:

b, e, f, j, l, m, p, s, u, x, z