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: ['9923', 'x', '1901', 'v', '1459', '7503', '3829', '4929', 'k', 'c', '3329', '8793', 'n', 'a', '7249', 'b', 'l', 'l', 'm', 'p', 'b', 'a']

Output: a, b, c, k, l, m, n, p, v, x


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

Output: b, e, n, t, y


Input: Consider Input: ['3269', 'w', '8107', 'c']


Output: c, w