You are given a code:

def main_solution(x):
    return func_20(func_20('bdku', 'qufr'), func_15('wrq'))

Can you predict the output of `main_solution("tvioiknt")` 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": "tvioiknt"}, "ref_output": "b\u00abqwd\u00bbu\u00abkrf\u00bbu\u00abrq\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_20('bdku', 'qufr'), func_15('wrq'))", "funcname": "main_solution"}
rule