You are given a code:

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

Can you predict the output of `main_solution("vakz")` 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": "vakz"}, "ref_output": "\u00abive\u00bbk\u00abtae\u00bbj\u00abjke\u00bbt\u00abkze\u00bbi", "ref_code": "def main_solution(x):\n    return func_20(func_15(x), func_9('iektej'))", "funcname": "main_solution"}
rule