You are given a code:

def main_solution(x):
    return func_20(func_15(x), func_9('ofaaim'))

Can you predict the output of `main_solution("avfmu")` 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": "avfmu"}, "ref_output": "\u00aboaf\u00bba\u00abavi\u00bbm\u00abmfi\u00bba\u00abamf\u00bbo\u00abu\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15(x), func_9('ofaaim'))", "funcname": "main_solution"}
rule