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: ['8235', 't', '1695', '9899', '3633', 't', '1823', 'r', 'x']

Output: r, t, x


Input: Consider Input: ['r', 'n', '7583', '8697', '7927', 'l', '5003', '1363', 'p', 'e', 'q', '6227', '6915', '8619', '9011', 'n', '3063', '3799']

Output: e, l, n, p, q, r


Input: Consider Input: ['y', '4265', '7595', '5439', '2961', '9599', '7569', 'a', 'y', 'l', 't', 'b', 'f', 'n', 'j', '2447', '315', 'l', '571', 'w', 'p', '9887', 'i', 'p']


Output: a, b, f, i, j, l, n, p, t, w, y