You are given a code:

def main_solution(x):
    return func_20(func_1('arrkh', 3), func_15(x))

Can you predict the output of `main_solution("xvflber")` 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": "xvflber"}, "ref_output": "a\u00abrxr\u00bbk\u00abhva\u00bbr\u00abrfk\u00bbh\u00abalr\u00bbr\u00abkbh\u00bb\u00abe\u00bb\u00abr\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_1('arrkh', 3), func_15(x))", "funcname": "main_solution"}
rule