You are given a code:

def main_solution(x):
    return func_20(func_20('ahfl', 'xgp'), func_15('qhvz'))

Can you predict the output of `main_solution("atzfjv")` 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": "atzfjv"}, "ref_output": "a\u00abxqh\u00bbg\u00abfhp\u00bbl\u00abv\u00bb\u00abz\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_20('ahfl', 'xgp'), func_15('qhvz'))", "funcname": "main_solution"}
rule