You are given a code:

def main_solution(x):
    return func_20(func_15('unt'), func_13('axrl', '-'))

Can you predict the output of `main_solution("oyvidn")` 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": "oyvidn"}, "ref_output": "\u00abau-\u00bbx\u00ab-nr\u00bb-\u00ablt\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15('unt'), func_13('axrl', '-'))", "funcname": "main_solution"}
rule