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: ['t', 'x', '1699', '8727']

Output: t, x


Input: Consider Input: ['2697', 's', '8733', 'n', '5871', 'f']

Output: f, n, s


Input: Consider Input: ['g', 'e', '2707', 'a', '5919', 'q', 'f', 'u', '5741', '5529', '9065', '4307', '9921', 'l', '5575', 'a', 's', '1935', '3183', '6791', '6047', '9773', '6543', 'o', 'i', 'i', 'f', '4573', '9769', '8801', '3303', 'e']


Output: a, e, f, g, i, l, o, q, s, u