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.

Input: Consider Input: ['5737', 'b', 'e', 't', '7419', 'n', 'y', '5225', '6485', 'b', '1343']

Output: b, e, n, t, y


Input: Consider Input: ['7591', '7521', 'm', '1429', 'x']

Output: m, x


Input: Consider Input: ['3715', 'k', 'w', 'x', 'p', '7741', '8027', '8221', '7691', 'o', 'x', 'd', '5361', '3141', '4443', '2313', 'a', '9905', 'u', 's', 'x', 'p', '6905', '1671', 'k', '9359', 'q', '5477', '4975']


Output: a, d, k, o, p, q, s, u, w, x