Detailed Instructions: 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.
See one example below:
Problem: ['8129', 'a', '4245', 'y', 'm', 'a']
Solution: a, m, y
Explanation: Here, the unique alphabets in the list are 'a', 'y', and 'm', hence their sorted order is 'a, m, y'.

Problem: ['1931', '5817', 's', '2643', 'c', 'x', '2615', '3111', '5865', '3225', 'j', '5803', 'k']
Solution:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
c, j, k, s, x