You are given a code:

def main_solution(x):
    return func_20(func_22(x), func_15('dtnc'))

Can you predict the output of `main_solution("prbmbvlwg")` 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": "prbmbvlwg"}, "ref_output": "p\u00abrdb\u00bbm\u00abbtv\u00bbl\u00abwn\u00bb\u00abc\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_22(x), func_15('dtnc'))", "funcname": "main_solution"}
rule