You are given a code:

def main_solution(x):
    return func_20(func_15(x), func_5('skul', 'rpp'))

Can you predict the output of `main_solution("ajrb")` without writing any code? Please reason and put your final answer in the following json format: {"output": <your output>}, where <your output> should be the final string.
user
{"ref_input": {"x": "ajrb"}, "ref_output": "\u00abrap\u00bbp\u00absjk\u00bbu\u00ablr\u00bb\u00abb\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15(x), func_5('skul', 'rpp'))", "funcname": "main_solution"}
rule