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.

Q: ['d', 'g', '9019', '9987', '8713', '9513', 'a', '2043', 'd', '5817', 'w', 'd']

A: a, d, g, w
****
Q: ['b', 'd', '8153', 'u', '3695', '5317']

A: b, d, u
****
Q: ['i', 's']

A:
i, s
****