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]: ['h', 'g', '4563', 'v', 'm', '107']
[A]: g, h, m, v


[Q]: ['5011', 'l', '925', 'e', 'b', '3077', 'm', '4541', '781']
[A]: b, e, l, m


[Q]: ['m', 'g', 'j', '65', 'a', 's', 'w', '4143', '5901', '3471', 'e', 'p', '5251', '3341', '7177', '4013', '1047', '381', '6055']
[A]:
a, e, g, j, m, p, s, w