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: ['h', 'u', 'y', '7677', '9441', '1769', 'v', '1433', 'l', '7739', 'a', '8305', 'n', 'a', '6711', '3161', 'e', 'u', '993', '2211', '4011', 'q', 'o']

Output: a, e, h, l, n, o, q, u, v, y


Input: Consider Input: ['5971', 'x', 'c']

Output: c, x


Input: Consider Input: ['2425', '7437', 'p', '9575', '2907', '8977', '7663', '6409', 'e', 'g', '3673', '7355', '7977', 'd', '9067', 'i', '2185', 'a']


Output: a, d, e, g, i, p