You are given a code:

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

Can you predict the output of `main_solution("ndoyb")` 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": "ndoyb"}, "ref_output": "n\u00ab-ed\u00bb-\u00aboh-\u00bby\u00ab-cb\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_13(x, '-'), func_15('ehc'))", "funcname": "main_solution"}
rule